Improved Rubber Compound for Tracked Vehicle Track Pads

Home , Nitrile rubber

~" ' Nil II II II Nil I Mill II Ml II I II J European Patent Office *%c\a n« © Publication number: 0 326 394 B1 Office_„. europeen des brevets

@ Date of filing: 27.01.89

© Priority: 29.01.88 US 105107 8702 Triumph Ct. Alexandria, VA 22308(US) @ Date of publication of application: Inventor: Rodriguez, Gumerslndo Jr. 02.08.89 Bulletin 89/31 608 Gettysburg Lane Fredericksburg, VA 22401 (US) © Publication of the grant of the patent: Inventor: Butler, Daniel Patrick 05.05.93 Bulletin 93/18 6509 Virginia Hills Avenue Alexandria, VA 2231 0(US) © Designated Contracting States: Inventor: Crawford, Dawn Marie AT DE FR GB SE 90 Autumn Drive South Stafford, VA 22554(US) © References cited: Inventor: Teets, Alan Roy EP-A- 0 139 044 5507 Hemlng Avenue GB-A- 2 163 170 Springfield, VA 221 51 (US) US- A- 4 585 826 Inventor: Feuer, Henry Otto 14237 Savannah Drive © Proprietor: THE UNITED STATES OF AMERICA Woodbrldge, VA 22193(US) as represented by the Secretary, United Inventor: Flanagan, David Paul States Department of Commerce 4304 Pembrook Village Drive National Technical Information Service, Of- Alexandria, VA 22309(US) fice of Government Inventions and Patents, 5285 Port Royal Road Springfield, Virginia 221 61 (US) © Representative: Jump, Timothy John Simon et 00 al @ Inventor: Touchet, Paul Venner Shipley & Co. 20 Little Britain Oi 12204 Harbor Drive London EC1A 7DH (GB) CO Woodbrldge, VA 22192(US) CO Inventor: Gatza, Paul Edwards CM 00 Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid (Art. 99(1) European patent convention). Rank Xerox (UK) Business Services (3. 10/3.6/3.3. 1) EP 0 326 394 B1

Description

This invention generally relates to an improved rubber compound, and more specifically relates to the improvement of the elastomeric components for tread pads of tracked vehicles, especially endless track 5 military vehicles. Track laying vehicles wherein a continuous track is constantly layed down in the direction of movement of the associated vehicle are well known. Examples of such track laying devices are the military tanks and personnel carriers. Such devices have an endless track with a plurality of linked metal track shoes. These military tracked vehicles and other commercial type tracked vehicles are frequently equipped with rubber track pads, rubber blocks or endless - band rubber track to reduce shock, noise, wear io and damage to road surfaces. These endless tracks render the vehicles operational in rough, uneven terrain when necessary under military manoeuvres. The vehicles, however, also travel over roads and hard surfaces and therefore the elastomeric components of the endless tracks should be of the type that wears well under abrasive rough terrain conditions. One example of a suitable track laying structure is disclosed in U.S. Pat. No. 3,078,128 issued Feb. 19, 1963 to the United States of America. Examples of previous tank 75 tread pads and related compositions are well defined in various other prior U.S. patents such as No. 3,781,067; No. 4,279,448; No. 4,587,280; No. 4,461,516; and No. 4,470,641. Historically, field performance of these elastomeric track pad components has been poor, especially for the medium to heavy tonnage tracked vehicles, 40 - 60 Tonnes (Tons). The service life of these tank pads is affected not only by the terrain and environmental conditions but also by the speed, cornering, braking, 20 weight of the vehicle, and the track tread design. While the operational life of the metal components is approximately 8000km (5000 miles) for vehicles of the 55 Tonne (Ton) weight class, the average life of the rubber pads is seldom more than 2400km (1500 miles under the best circumstances, and is usually less than 800km (500 miles) under the severest conditions. The elastomeric components of an endless track are affected in several ways depending upon service. Directly, it can cause cuts, tears, chunking, blow-outs 25 and abrasive wear. Indirectly, it causes damage through hysteretic heating, environment convection and surface/terrain heating. Those skilled in the art are aware of the types of failures on rubber tank track pads, roadwheels and rubber blocks requiring frequent and costly replacement of the elastomeric components. Track pads for shoes presently are made from styrene - butadiene rubber (SBR). The widespread use of SBR in track pad applications appears to be based on cost, historical precedent and the fact that at times 30 the United States Government has required that the materials used in their devices be available from sources within the United States to insure a continued supply. These factors in many ways are detrimental to the policy of continuing to use natural rubber for track pads and some shoe components, particulary since natural rubber is not available within the United States. Therefore, it is of the utmost importance to develop and use improved synthetic rubbers to improve the performance of tank track pads and shoes. 35 To improve field or service performance of tank pads, one must first identify those properties that are most needed and then optimize these. This is by no means a trivial task. Those skilled in the art would agree that to improve performance of pads and shoes, properties such as cutting and chipping resistance, tear and tensile strength, crack growth resistance, abrasion resistance, hysteresis and thermomechanical stability all have to be improved. 40 The primary object of the present invention is to overcome the aforementioned problems associated with prior track pads by providing an improved elastomeric composition which is particularly adaptable for fabricating track pads having improved resistance to cuts, tears, chunking, blowouts and abrasive wear. A further object of the present invention is to provide such a novel elastomeric composition of matter having many uses including for other related products such as road wheels, bushing members, gun 45 abutment stops useful for association with tank track systems and other military armament/equipment. Other objects and advantages of this invention will become more apparent from the following detailed description, with the novel features, arrangements and combinations being clearly pointed out in the specification as well as in the appended claims. In accordance with the present invention, it has been found unexpectedly that the above objects and 50 advantages are accomplished by our novel track pad composition by our novel selective use of polymers, fillers, the curing system and the proper processing thereof from which to make pads, shoes, bushings, solid rubber roadwheel surfaces and other items having greatly improved service life, as summarized in the following. Accordingly, in a first aspect, the present invention provides a vulcanizable elastomeric composition 55 comprising a combination of respective polymer, filler, curing, and antidegradant systems, wherein (A) said polymer system is selected from a group including (a) about 100 parts by weight of highly saturated nitrile polymer;

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(b) a blend of from 80 to 90 parts by weight of highly saturated nitrile polymer, and of from 10 to 20 parts by weight of carboxylated nitrile; and (c) a blend of from 45 to 90 parts of highly saturated nitrile polymer, and of from about 1 to a maximum of 5 parts of carboxylated polymer, and of from 5 to 50 parts of nitrile rubber; and 5 (B) said curing system comprises (a) from 1 .5 to 30 parts by weight of a metallic oxide; selected from a group including at least zinc oxide and magnesium oxide; (b) from 25 to 50 parts by weight of a metallic methyl - methacrylate resin selected from a group including at least a zinc methyl - methyacrylate resin and a zinc dimethyl - methyacrylate resin; io (c) a curative compound of from .25 parts to 3 parts selected from the group including (i) dicumyl peroxide, (ii) derivatives of dicumyl peroxide; (iii) sulfur, and (iv) sulfur donor chemicals. is It is to be understood that for the purpose of this invention, the term "vulcanize" is used in its broadest sense to include all means of cross - linking rubbery polymers both with and without the use of elemental sulfur. The improved composition tank pads should include at least one surface portion, preferably the portion which contacts the ground, made of an elastomeric material comprised of a combination of polymer, filler, 20 curing and antidegradant systems in accordance with the first aspect of the invention. Thus, the polymer system may comprise a pure or a blend polymer system as aforesaid. The highly saturated nitrile polymers in the polymer system, preferably, have a degree of unsaturation ranging between 1% and 20%. The filler system may comprise from 15 to 25 parts of a highly reinforcing small particle carbon black 25 such as any of those designated as N-110, N-121, N-220, or N-330 by ASTM D-1765; or it may alternatively comprise a medium processed channel black. The curing system relates to or embodies the ingredients which will be activated to achieve the cross - linking of the polymer chain in the compound and the antidegradant system, preferably, is comprised of at least one antioxidant which among others may comprise from 0.25 to 2 parts of a polymerized 1,2- 30 dihydro- 2,2,4 -trimethyl -quinoline (TMQ). It is to be understood that for each of the foregoing four systems, that the stated parts are to be by weight per 100 parts of the selected polymer system. In a second aspect the present invention provides a process for preparation of a vulcanizable elastomeric composition comprising blending a mixture of A. about 100 parts by weight of highly saturated nitrile polymer; 35 B. from 15 to 25 parts by weight of a highly reinforcing filler, C. a curative mixture comprising (a) from 1.5 to 30 parts by weight of a metallic oxide selected from a group including at least zinc oxide and magnesium oxide; (b) from 25 to 50 parts by weight of a metallic methy - methacrylate resin selected from a group 40 including at least a zinc methyl - methacrylate resin and a zinc dimethyl - methacrylate resin; (c) a curative compound of from 0.25 parts to 3 parts selected from the group including (i) dicumyl peroxide, (ii) derivatives of dicumyl peroxide; (iii) sulfur, and 45 (iv) sulfur donor chemicals; and D. an antidegradant mixture comprising from 0.25 to 2 parts by weight of an antioxidant selected from the group including at least the antioxidants from the respective families of (a) quinolines, (b) substituted para-phenylenediamine (PPD), and 50 (c) hindered bisphenols. In a third aspect the invention provides a process for making a compression - molded track pad product which product includes an assembly with metal - mounting plates in combination with the vulcanizate obtained from a composition in accordance with the first aspect of the invention, said process including the steps of: 55 A. making a predetermined size preform block of the vulcanizable composition; B. coating the metal mounting plates with a suitable heat - activated adhesive; C. preheating said preform block to about 82° C (180° F); D. preheating said metal mounting plates also to about 82° C (180° F);

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E. assembling said mounting plates and said preform into a mold which has been preheated to about 165° C (330° F)., which corresponds to a preset temperature of a compression press; F. closing said mold and said compression press, while maintaining the press temperature of about 177°C (350 °F).; 5 G. simultaneously maintaining a minimum pressure of about 13.8bar (200 p.s.i.) within said mold for a period of about 80 minutes; and H. thereafter removing said product from said press and compression mold. In a further aspect the present invention provides a vulcanizate product made by heating and compression molding a composition in accordance with the first aspect of the invention via the use of io applicable molds and requisite related product inserts to which the vulcanizate is bonded, said vulcanizate product being of a predetermined size and shape to constitute a particular elastomeric component family member of a group of elastomeric family component members including track pads, road wheels, and bushing members all useable in conjunction with a tank track system. In a final aspect the invention provides a vulcanizable product member formed according to a process is in accordance with the second aspect of the invention for which said product member may constitute any one of various elastomeric -containing family component members of various selected, respective family groups embodying (a) tank track components including at least track pads, road wheels, and related bushing members all useable with tank track systems; 20 (b) various elastomeric abutment and stop or limit members repetitively engageable by moving mechanisms; and (c) various at least semi -flexible baffle and skirt family members useable with various air cushion type vehicles; said product member formation utilizing known compression molding equipment and subassembly proce - 25 dures in conjunction with associated bondable metallic and non - metallic product components, and wherein for at least certain family members said elastomeric composition is suitable preformed as by extruding and shaping into predetermined size blocks which thereafter are respectively preheated and assembled with the respective associatable bondable product components, such as pad - mounting plates, wheel hub members and bushing sleeves, into a requisite shaped preheated mold, and 30 wherein the vulcanizate end product is formed by requisite heating and compression molding proce - dures. The rubbery or elastomeric composition of the present invention can be prepared and compounded using any of the conventional compounding and mixing techniques using conventional rubber processing equipment such as a Banbury mixer or mixing mill. The unvulcanized rubbery composition is then pre- 35 formed through a rubber extruder and larger amounts or thicknesses are pre - heated before assembling it with any applicable metal insert sub -assembly component or plate member together with a suitable heat- activatable adhesive which are then placed into a mold for the particular configuration article such as a tank track pad, bushing, shoe and/or solid tire or other product. A vulcanization temperature of at least 320 degrees Fahrenheit should be used to fully activate the peroxide curing system when making our highly 40 improved tank track pads. Premature partial vulcanization must be avoided from the normal or inherent heat generated during the use of the mixing equipment. Therefore, mixing apparatus of a type provided with cooling means is preferably utilized. The track pads after vulcanization are of improved construction with the rubbery composition exhibiting a relatively high abrasion resistance, high cutting and chipping resistance, high tear and tensile strength at 45 high temperature, decreased hysteresis, high resistance to fire and to cracking or crack propagation, and shows good product uniformity and good thermo - mechanical stability, with supporting test results being described in the following detailed description. Preferred embodiments of the invention are described in the dependent sub -claims 2-12 (2-10), 14-23 (12-21), 27 (25) and 28 (26). The numbers in parenthesis identify the claims for contracting states 50 DE, FR and GB. FIG. 1, 2 and 3 are a transverse cross - sectional views through various types of exemplary track shoes or pads made of our new composition; FIGS. 4 and 5 are top plan and cross - sectional views respectively for an M - 60 form of track shoe utilizing our new composition and process; 55 FIG. 6 is a diagrammatic fragmentary elevational view showing a large bore gun which utilizes a shock absorbing abutment which is comprised of our improved composition; FIG. 7 is a diagrammatic side view of an air cushion type of vehicle which can utilize flexible skirts made of our new composition.

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Referring in greater detail to FIG. 1, there is shown one illustrative form of a track shoe 10 of generally conventional overall design. This particular shoe includes three circular metal tubes 12, 14, and 16 extending between two metal end plates, not readily visible in the drawings. Each end plate has an upper flat edge 22, a lower flat edge 22 and two circular end edges 20. In practice, each track section comprises 5 two track shoes 10 arranged in side -by -side relation, as shown for example in U.S. Pat. No. 4,165,906 to J.O. Fix. Non - illustrated connector pins and elastomeric bushings extend through tubes 12 and 16 into connector links to interconnect the track sections to adjacent track sections. The various track shoes 10 making up a complete endless track are structurally identical. These Figures 1 and 2 and much of their description are copied from U.S. Patent 4,461,516. io In the illustrated track shoe the space between the two end plates is occupied by a resilient elastomeric pad 24 having a terrain - engagement surface 26. Upper surface 28 of the elastomeric pad is engaged by a non - illustrated road wheel carried on a swingable suspension road arm in conventional fashion. Our improved composition is particularly useful for making very substantively improved track pads of various forms and shapes. 75 FIG. 2 illustrates a second type of track shoe with a pad 36 of our improved composition. The shoe comprises a metal casing 32 that includes a web 34 and two tubes 12 and 16 adapted to receive non- illustrated connector pins. The elastomeric pad 36 is removably received in a cavity on the lower face of web wall 34 between the tube outer surfaces. Retention of the improved pad 36 in the cavity is accomplished by a screw or stud 38 extending from a backing plate 46 into a nut 40. The upper surface of 20 web wall 34 has a elastomeric member 42 molded thereon to provide a flat runway surface 44 for non - illustrated road wheel. The improved composition tank pads should include at least one surface portion, preferably the portion which contacts the ground, made of our improved elastomeric material comprised of a unique combination of a polymer system, a filler system, a curing system, and an antidegradant system. The polymer system 25 may comprise a pure or a blend polymer system such as: (A) 100 parts of highly saturated nitrile polymer, or alternatively (B) a blend of from 80 parts to 90 parts of highly saturated nitrile, and from 10 parts to 20 parts of carboxylated nitrile; or still further alternatively (C) a blend of from 45 parts to 90 parts of highly saturated nitrile, and from 1 to a maximum of 5 parts of 30 carboxylated nitrile, and from 5 to 50 parts of nitrile rubber. The filler system may comprise from 15 to 25 parts of a highly reinforcing small particle carbon black such as any of those designated as N - 1 1 0, N - 1 21 , N - 220, or N - 330 by ASTM D - 1 765; or alternatively and preferably may comprise medium processed channel black. The carbon black filler system may also be blended to include parts of silica materials such as from 1 to 15 parts of fumed silica which silica 35 contributes to the overall 15-25 parts by weight of the highly reinforcing filler material. The total filler system should not exceed the aforestated maximum of 25 parts by weight of 100 parts. The curing system herein relates to or embodies the ingredients which will be activated to achieve the cross - linking of the polymer chain in the compound. The curing system preferably includes from 1.5 to 30 parts of a metallic oxide such as zinc oxide or magnesium oxide; and further from 25 to 50 parts by weight 40 of a metallic methyl - methacrylate resin which may be selected from a group including a least zinc methyl - methacrylate resin and zinc dimethyl - methacrylate resin; and still further includes a curative compound of from 0.25 parts to 3 parts by weight selected from a group including (i) dicumyl peroxide, (ii) derivatives of dicumyl peroxide, (iii) sulfur, and (iv) various sulfur donor chemicals. It is to be noted that any use of sulfur donor chemicals will depend upon the degree of saturation or 45 unsaturation of the highly saturated nitrile. For example, when the formulation of claim 1 hereinafter includes highly saturated nitrile having degrees of unsaturation of approximately 5%, or of approximately only 2.5%, respectively, a curative compound may include one of various sulfur donor compounds. Two preferred examples thereof include (i)N- cyclo - hexyl - 2 - benzothiazole sulfenamide, and 50 (ii) tetra - methyl - thiuram disulfide. The antidegradant system is comprised of from 0.25 to 2.0 parts by weight of at least one antioxidant selected from the group including at least the antioxidants from the respective families of (a) quinolines, (b) substituted para-phenylenediamines (PPD), and (c) hindered bisphenols. One preferred antioxidant will consist of from 0.25 to 2.0 parts by weight of polymerized 1,2, dihydro- 2,2,4 -trimethylquinoline (TMQ). 55 Another may comprise a substituted para-phenylenediamine (PPD) which is N - Isopropylphenyl - p - phenylenediamine. A nitrile rubber may be defined as a straight chain copolymer of a diene and an unsaturated nitrile, the more common being the copolymer of butadiene and acrylonitrile. The majority of nitrile rubbers which are

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available today are made by copolymerizing these two monomers. Nitrile rubber is available in several standard grades of oil resistance based on the acrylonitrile content of the polymer ranging from 18 to 50%, with 34% being a common typical figure for a general purpose grade. Generally, the grades are referred as to very high, high, medium high, medium, medium low, and low acrylonitrile content. The following is a chemical representation of each of the two monomers separately, and of the resulting copolymer, nitrile rubber (NBR).

BUTADIENE ACRYLONITRILE 10 CH2=CH-CH-CH CH2=CH-CN NITRILE RUBBER (NBR) ( (CH2-CH=CH-CH2) (CH2— CH) )n 15 1 CN

The very high and high acrylonitrile polymers are used where the utmost in oil resistance, aromatic 20 fuels, and solvent resistance is required. The medium grades are used in applications where greater swelling of the rubber is tolerable. The low and medium low acrylonitriles are used where low temperature flexibility is of greater importance. However the polymer used in this subject invention application rubber formulation is a highly hydroge - nated nitrile copolymer with slight double bonds. Highly saturated nitrile rubbers, HSN, are presently 25 produced by the selective and controlled hydrogenation of nitrile rubber, NBR. Examples of such copolymers are disclosed in U.S. Patent 4,337,327; 4,384,081; 4,464,515; 4,503,196; and German Patents 2,539,132 and 2,913,992. At least three companies are known to produce highly saturated nitrile copolymers useful in the practice of this invention and having with various degrees of hydrogenation. Mobay Corporation in Pittsburg, Pa. 15205-9741, produces at least two grades of HSN's under the commercial name of 30 "THERBAN". Polysar Ltd. in Akron, Ohio, 44313, produces at least three grades of HSN's under the trade name of "TORNAC". Nippon Zeon Co., Ltd. in New York City, 10017, produces at least three grades of HSN's under the trade name of "ZETPOL". Grades determined by degree of unsaturation of the HSN, typically 5%, 2.5%, and 1%, respectively. A carboxylated nitrile copolymer, XNBR, is the resulting polymer from the modification of a nitrile 35 copolymer, NBR, to include carboxylic groups in the copolymer chain. This type of polymer contains in addition to acrylonitrile and butadiene, one or more acrylic -type acids as part of the comonomer system. The polymerization of these monomers produces a chain similar to a normal nitrile rubber except for the carboxyl groups which are distributed along the chain with a frequency of about 1 to every 100 to 200 carbon atoms. 40 This type of polymer is unique in that it can be vulcanized by reactions of the carboxylic group as well as conventional sulfur -type vulcanization. This polymer has been used in a blend with HSN's in the rubber formulation subject of this invention because the carboxy modification exhibits much higher tensile strength and modulus, lower elongation, higher hardness, much improved hot tear and tensile strength, better low- temperature brittleness, improved ozone resistance, and better retention of properties after air aging at high 45 temperatures, all important properties for tank pad performance. Carboxylated nitriles, XNBR, suitable for the practice of the invention are produced by most nitrile rubber, NBR, manufacturers. B.F. Goodrich Co. produces XNBR'S under the commercial trade name of "HYCAR" while the Goodyear Co. produces XNBR'S under the name of "CHEMIGUM". Both companies; have business locations in Akron, Ohio. 50 Up to 50% of total nitrile component of the inventive composition can be of a standard grade of nitrile copolymer, i.e., not highly saturated nitrile, without significant degradation of performance as a track pad material. This can significantly reduce the cost of the pad. Recommended quantities are from 5 parts to 50 parts standard nitrile rubber per 100 parts total nitrile copolymer in the inventive composition. One preferred and fully tested composition contains 100 parts of HSN as the polymer system. 55 The following example is a representative comparison of our newly developed composition versus commercially procured pads which were field tested on a military M-60 tank and on a much heavier experimental military vehicle known as a Counter Obstacle Vehicle (COY). The tests for the COY were conducted at the Ft. Belvoir, Virginia Engineering Proving Grounds, more particularly to measure for thermal

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buildup, abrasion resistance, adhesion resistance, chunking and chipping, and all terrain mobility. The M - 60 tank tests were conducted at the Yuma, Arizona Proving Grounds and more particularly directed to operation on paved roads, hilly cross-country terrain, and various overall terrain combination tests.

5 EXAMPLE

A rubbery composition was prepared and compounded according to the present invention by mixing in a basically conventional manner 100.0 parts of highly saturated nitrile polymer (HSN), 2.0 parts zinc oxide, 0.5 parts 1,2-dihydro-2,2,4-trimethylquinoline (TMQ), 20.0 parts carbon black, 30.0 parts zinc methyl - io methacrylate resin, and 1.3 parts dicumyl peroxide. The unvulcanized rubbery composition was then preformed through a rubber extruder, preheated to 82 °C (180°F), placed in the desired mold, and vulcanised at about 165°C (330 ° F) for 80 minutes. The HSN Polymer was obtained commercially from Goldsmith Eggleton, Akron, Ohio with the trade name "ZETPOL 2020". The TMQ antioxidant was obtained commercially from R.T. Vanderbilt in Norwalk, CT. with the name "AGERITE RESIN D". The carbon black is was obtained commercially from Summit Chemical Co. under a trade name known as "MPC BLACK". The zinc methyl - methacrylate resin was obtained commercially from Yardley Ball Corp. in Yardly, Pa. with the trade name "Z-MAX MA". The dicumyl peroxide curative was obtained commercially from the Hercules Co. in Akron, Ohio, with the trade name "Dl CUP R". In order to form the sample test track pads, the extruded preheated rubber was assembled with applicable metal inserts and a heat - activated adhesive into 20 a mold where vulcanization was carried out in a heated press. The physical properties of the resulting new pads were measured and are presented and are compared in Table 1 below to those of standard commercial pads as tested. The track pads designated STD. T-107 and STD T-142 tested were standard stock pads for the Army's experimental Counter Obstacle Vehicle (COV), and the M - 60 tank respectively, made from styrene - butadiene rubber (SBR) and are of the type presently employed on military tracked 25 vehicles. The specific formulation of the standard pads is proprietary to the manufacturer and not known by the inventors, but it can be characterized as a common type of styrene - butadiene vulcanizate.

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TABLE 1 PROPERTIES OF ELASTOMERIC PAD COMPOUNDS

COV M-60 OUR NEW STANDARD STANDARD PROPERTIES COMPOUND T-107 T-142

ORIGINAL TENSILE STRENGTH. (PSI) bar (3960)273(3010)208 (28201195 200% MODULUS. (PSI) bar (843)58 (780)54 (580)40 ELONGATION. % 570 520 510 SHORE A HARDNESS. PTS 78 64 69 BASHORE REBOUND. % 30 26 36 SPECIFIC GRAVITY 1.1373 1.1685 1.1559 40% COMPRESSIBILITY .(PSI) bar (966)67 (495)34 (510)35 TEAR STRENGTH. DIE C UNAGED. (Lbs /In) kg /cm (449)79 (266) 47 (310)55 AT 121° C (250°F) (Lbs/In) (234>m (152) 27 (115)20 Kg/cm ABRASION TABER. GR/1000 CYCLES .0015 .0308 .0364 PICO RATING 691 790 101 GOODRICH CUTTING AND CHIPPING DIAMETER LOSS. (INCHES) cm (. 0540). 1 37 (2320). 589 (0820) 20) WEIGHT LOSS. GRAMS .7500 3.1540 1.1450 DYNAMIC PROPERTIES GOODRICH FLEX TEMPERATURE RISE INTERNAL. °C 84 72 50 EXTERNAL. °C 58 30 30 BLOW OUT TIME. MIN. 5 24 37 DEMATTIA FLEX CRACK GROWTH UNAGED. MILS /MIN. 6 26 24 20 HRS AT (250° F) 121° C 12 264 435 MILS/MIN. CRACK INITIALIZATION, CYCLES X 103 110 8.7000 18 AFTER OVEN AGING 70 HRS AT (250°F)121CC ELONGATION RETENTION. % 81 12 38 TENSILE RETENTION. % 100 45 57

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The above tests were carried out according to accepted Industry Standards as listed in Tables 2 below:

TABLE 2 PROPERTY TESTS 1. MOONEY VISCOSITY AND CURVE ASTM D 1646 2. RHEMETER DATA AND CURVE ASTM D 2084 3. PROPERTIES OF CURED RUBBER RUN AT ROOM TEMPERATURE A. SPECIFIC GRAVITY ASTM D 792;PARA 15 B. TENSILE STRENGTH ASTM 412 C. ELONGATION ASTM 412 D. 100,200, AND 300% MODULUS ASTM 412 E. HARDNESS, IRHD AND SHORE A ASTM 1415 F. RESILIENCE, BASHORE REBOUND ASTM 2632 6. TEAR STRENGTH, DIE B AND ASTM 624, DIES DIE C B AND C H. TROUSER TEAR WITH FABRIC INSERT I . ABRASION, TABER ASTM D 3389 J. ABRASION, PICO ASTM D 2228 K. COMPRESSIBILITY L. DISPERSION RATING AS OBSERVED UNDER A 60 POWER MICROSCOPE AND DARKFIELD REFLECTED LIGHT MICROSCOPE M. PUNCTURE RESISTANCE N. CUTTING AND CHIPPING PROPERTIES ON CURED MATERIALS RUN AT (250 °F, 300 °F) 121° C, 149°C A. TEAR STRENGTH, DIE B ASTM D 624, DIES AND DIE C B AND C B. TROUSER TEAR WITH FABRIC INSERT C. COMPRESSIBILITY D. PUNCTURE RESISTANCE E. TENSILE, ELONGATION, AND MODULUS AjTl60oF, 212°F ASTM D 412 AND 250oF;71oC, 100" C, 121*0. FLEX FATIGUE TESTS: A. DEMATTIA AND ROSS CUT GROWTH UNAGED, AFTER AGING 70 HOURS AT 100°C (212° F ) AND AFTER AGING ASTM D813 20 HOURS AT (250° F) 121°1 21° C (RUN ASTM D430 AT 121° C (250° F) ) METHOD B B. DEMATTIA CRACK INITIATION C. GOODRICH FLEX ATAT(122oF)50°C (122°F)50°(122°F)ro° C ASTM D 623, METHOD A USING A (.175IN.) 0.44cm STROKE AND 9.766bar (141.6PSI) FOR DETERMINING HEAT BUILD-UP AND USING A 0.76cm (0.30 IN.) STROKE WITH (141.6)9.766 OR (265. PSI) 18.3bar PRESSURE FOR BLOW-OUT TEST ROSS FLEX CRACK GROWTH UNAGED, AFTER AGING AT(212°F) 1 00° C AND RUN AT (250° F), 121" C ASTM D 1052 EP 0 326 394 B1

6. OZONE RESISTANCE ASTM D 1149 AND D518 METHOD B 7. BRITTLENESS AT (- A0°F)-40*C ASTM D 21137 8. PEEL ADHESION INITIALLY ASTM D 429, AND AT (250°F) 121°C METHOD B AND MIL-T-1189 ID, PARA 4.6.7.3 10 DSC & DTA OF UNAGED & AGED SAMPLES

is Some of the more important properties for track pad applications are: 1 . Cutting and chipping resistance. 2. Tear strength, (ambient and high temperature). 3. Crack growth resistance, (ambient and high temperature). 4. Fatigue life under compressive stresses. 20 5. Low heat build - up and high abrasion resistance. The statistics set forth hereinabove in Table 1 show the superiority in the properties of our improved elastomeric compound over that use in the standard production pads. Data depicted in Table 1 is the result of tests conducted in the laboratory from molded T-107 and T-142 tank pads, COV and M-60 respectively. The geometry of both type of pads is different. Therefore, curing characteristics and polymer 25 flow patterns during vulcanization may produce small differences in the physical properties between the two types of pads. Analysis of the data depicted in Tables 1 and 2 show that the tensile strength of our improved elastomeric compound is 32% higher as used the T-107 pads and 40% higher for the T-142 pads. The retention of tensile strength after heat aging was 100% for the T-107's and T-142's. The standard 30 production pads retained only 45% of the tensile strength for the T-107's and 57% for the T-142 pads. The rebound and elongation was about the same for our improved pad as for standard compound. The hardness of the improved material is 22% higher for our improved composition in the T-107 pads and 13% higher for the T-142 pads. The increase in hardness produced a 95% improvement in the load bearing capabilities of our improved composition pads. Another significant improvement was achieved on 35 tear resistance with a 69% improvement for our improved composition in the T-107s and 45% for T- 142's at ambient temperature. Tear strength at high temperature produced improvement of 54% for our improved T-107 pads and double the tear resistance for our improved T-142 pads. Abrasion resistance is a very important property and was measured by two methods, Taber abrasion and Pico index, respectively. Both test methods indicated an improvement of 24 times better on Taber and 40 9 times better on Pico for our improved composition T-142 pads while for our improved T-107 pads the Taber was 20 times better but the Pico indicated a 12.5% decrease. The observed mode of failure for tank pads during crosscountry operations is chunking and chipping. This property was measured with the B.F. Goodrich Cutting and Chipping machine and both diameter and weight loss of the specimens were recorded. Test results for diameter and weight loss were in excellent agreement producing the same degree 45 of improvement for both types of our improved composition test pads. Our improved composition pads exhibited a 76% improvement for T-107 pads and 34% better for the T- 142's. The improved elastomeric tank pads exhibited a higher internal temperature when tested for heat build-up as well as during field testing. However, the unique combination of the highly saturated nitrile rubber and zinc - methylmethacrylate with the peroxide cure, produces an unparalleled heat resistance that 50 prevents premature failure. Crack growth resistance relates to the ability of a rubber compound to deter crack propagation once the rubber has been cut as happens during cross - country operations. Crack propagation deteriorates into tear and eventually chunking and chipping. Crack growth was measured using a Ross tester. Specimens were tested at ambient temperature and after being heat aged at 121 °C (250 ° F). In addition the resistance to 55 crack initiation was measured. Resistance to crack growth was 400% better at ambient temperatures for both our improved composition T-107 and T-142 elastomeric pads. At high temperature the crack growth resistance of our T- 107's was improved 22 times while for the T- 142's it was improved 36 times over the standard production compounds.

10 EP 0 326 394 B1

Two performance test programs were carried out using appropriately formed tank pads to compare the performance of pads of the standard styrene - butadiene composition to the inventive nitrile rubber composition on actual tracked vehicles. Two types of vehicles were employed to carry out the field tests, a Counter -Obstacle -Vehicle (COV) which is an engineering type tracked vehicle, weighing about 72 tonnes 5 (tons), and an M-60 battle tank weighing about 40 tonnes (tons). The testing of the COV pads, (T-107's) was performed over a severe course designed to combine all possible operational and terrain factors deemed relevant for the application. The test plan for the M-60 field test was designed to include three phases consisting of a (2000 mile) 3200km paved surface course, (900 mile) 1440km hilly cross-country course and a (1000 mile) 1600km combination course. All these tests were successfully completed by tank io pads made from our improved composition which is the subject of this invention. Complete results of the COV T-107 track pad field test and results from field test on the T-142 tank pads from the M-60 tank confirm that a distinct technological breakthrough in tracked vehicle pad performance has been achieved. The COV was initially tested for a total of (1600 miles) 2560km including portions in hard track and all type terrain. The wear of the pads with our new rubber formulation was is significantly less than the conventional rubber used for tank pads. Additional tests have confirmed the greatly improved performance beyond (3000 miles) 4800km with still no indication of failure, although some abrasive wear is evident. Projected results indicate that the pads with the new formulation will have a service life in excess of about 3500 miles while the standard production pads exhibit an average service life of (1200 miles) 1920km under similar testing conditions. 20 During the paved course portion of the M-60 field test, standard production pads failed on the average of (1200 miles) 1920km. The pads with our disclosed improved rubber formulation were tested for (2000 miles) 3200km, the maximum duration allocated in the test plan for the paved course. At the end of the test the limited wear of the new formulation pads indicated a projected service life of (3,400 miles) 5440km, a service level never before achieved by any conventional rubber pad. Subsequent actual field tests have 25 proven continued good useful life at over (3000 miles) 4800km on the same paved course. The above results show the superior service life of our improved elastomeric compound over that used in the standard pads. The service life of our improved composition pads on paved road is three times better than the standard pads. In the more severe cross - country operations the improved pads exhibit a service life of 2.5 longer than the standard pads. 30 It should be pointed out that there is the significant difference in weight between the M-60 and the COV; the M-60 weighs approximately 45 Tonnes (Tons) as opposed to the 72 tonnes (Tons) for COV. This weight difference by itself can account for the difference in pad performance between the two vehicles but the fact remains that for either vehicle our improved formulation exhibits up to more than double the service life of a standard production tank pad. 35 It is to be understood that because the highly saturated nitrile exhibited distinguishing characteristics of inherent ozone, heat and weather resistance which precluded deterioration both in the field and in storage, there was no need to include a separate antiozonant for precluding ozone attack. To add such an ingredient would be a wasteful, useless exercise. Additionally, the improved rubber formulation exhibited self extin - guishing characteristics when subjected to an open flame. It also exhibits resistance to chemical warfare 40 agent decontaminants. Exhibiting a tensile strength retention over 90% after immersion in a DS - 2 fluid for 24 hours. DS-2 is a U.S. Army general purpose decontaminant fluid for chemical warfare agents. From the foregoing detailed description, it is apparent that a greatly improved elastomeric composition has been developed which achieves all the objects and has the advantages set forth hereinabove. While some specific test examples have been described more particularly for tank track pad applications, it is to 45 be understood that other variations in the composition, and other potential uses such as abutments or stops for large bore guns, and flexible elastomeric skirts for air cushion type vehicles, are contemplated to be within the spirit of the invention. Accordingly, reference should be made to the appended claims for the governing scope hereof inasmuch as those skilled in the art may make various changes and modifications and other uses without departing from the spirit and scope of this invention. 50 Claims Claims for the following Contracting States : DE, FR, GB

1. A vulcanizable elastomeric composition comprising a unique combination of respective polymer, filler, 55 curing, and antidegradant systems, wherein: A. said polymer system is selected from a group including (a) about 100 parts by weight of highly saturated nitrile polymer;

11 EP 0 326 394 B1

(b) a blend of from 80 to 90 parts by weight of said highly saturated nitrile polymer and of from 10 to 20 parts by weight of carboxylated nitrile; and (c) a blend of from 45 to 90 parts of said highly saturated nitrile polymer, and of from 1 to a maximum of 5 parts of carboxylated polymer, and of from 5 to 50 parts of nitrile rubber; and B. said curing system comprises (a) from 1 .5 to 30 parts by weight of a metallic oxide selected from a group including at least zinc oxide and magnesium oxide; (b) from 25 to 50 parts by weight of a metallic methyl - methacrylate resin selected from a group consisting of at least a zinc methyl - methacrylate resin and a zinc dimethyl - methacrylate resin; (c) a curative compound of from .25 parts to 3 parts selected from the group including (i) dicumyl peroxide, (ii) derivatives of dicumyl peroxide; (iii) sulfur, and (iv) sulfur donor chemicals; C. said filler system comprises from 15 to 25 parts by weight of a highly reinforcing filler material, said filler material being selectable from the group including (a) medium processed channel black; and (b) carbon black particles of the type selected from a subgroup including N-110, N-121, N- 220, and N-330 as designated by ASTM D-1765.

The composition of claim 1, wherein said antidegradant system comprises from 0.25 to 2.0 parts by weight of an antioxidant selected from the group including at least the antioxidants from the respective families of (a) quinolines, (b) substituted para-phenylenediamines (PPD's), and (c) hindered bisphenols.

A vulcanizable elastomeric composition including a combination of respective polymer, filler, curing, and antidegradant systems, comprising: A. said polymer system is selected from a group including (a) about 100 parts by weight of highly saturated nitrile polymer; (b) a blend of from 80 to 90 parts by weight of highly saturated nitrile polymer, and of from 10 to 20 parts by weight of carboxylated nitrile; and (c) a blend of from 45 to 90 parts of highly saturated nitrile polymer, of from 1 to a maximum of 5 parts of carboxylated nitrile polymer, and of from 5 to 50 parts of nitrile rubber; B. said filler system comprising from 15 to 25 parts by weight of a highly reinforcing filler material; C. said curing system comprising (a) from 1 .5 to 30 parts by weight of a metallic oxide selected from a group including at least zinc oxide and magnesium oxide; (b) from 25 to 50 parts by weight of a metallic methyl - methacrylate resin selected from a group consisting of at least a zinc methyl - methacrylate resin and a zinc dimethyl - methacrylate resin; (c) a curative compound of from .25 parts to 3 parts selected from the group consisting of: (i) dicumyl peroxide, (ii) derivatives of dicumyl peroxide; (iii) sulfur, and (iv) sulfur donor chemicals; and D. said antidegradant system comprises from 0.25 to 2.0 parts by weight of an antioxidant selected from the group consisting of antioxidants from the respective families of (a) quinolines, (b) substituted para-phenylenediamines (PPD's), and (c) hindered bisphenols.

The composition of claim 1, wherein said filler system is modified to include a blend of said carbon black particles together with from 1 to 15 parts of fumed silica contributing to said overall 15-25 parts by weight of said highly reinforcing filler.

The composition of claim 2, wherein said antidegradant system consists of from 0.25 to 2 parts by weight of polymerized 1,2 dihydro- 2,2,4 trimethyl -quinoline antioxidant (TMQ).

12 EP 0 326 394 B1

6. The composition of claim 2, wherein said antidegradant system consists of from 0.25 parts to 2 parts by weight of a substituted paraphenylenediamine (PPD).

7. The composition of claim 2, wherein said antidegradant system comprises a substituted para- 5 phenylenediamine (PPD) which is N - isopropyl phenyl - p - phenylenediamine.

8. The composition of any of claims 1 , 2 or 3 in which said highly saturated nitrile polymer in paragraph A has a degree of unsaturation ranging between 2.5% and 5%; and wherein said curative compound consists of a tetra - methylthiuram disulfide. 7010 9. The composition of any of claims 1, 2 or 3 which includes highly saturated nitrile rubber, having a degree of unsaturation ranging between 1% to 20%, and in which said curative compound consists of dicumyl peroxide.

75 10. A vulcanizable elastomeric composition, as claimed in claim 1, wherein said polymer system consists of about 100 parts by weight of a highly saturated nitrile polymer.

11. A process for preparation of a vulcanizable elastomeric composition comprising blending a mixture of A. about 100 parts by weight of highly saturated nitrile polymer; 20 B. from 15 to 25 parts by weight of a highly reinforcing filler, C. a curative mixture comprising (a) from 1 .5 to 30 parts by weight of a metallic oxide selected from the group including at least zinc oxide and magnesium oxide (b) from 20 to 50 parts by weight of a metallic methyl - methacrylate resin selected from the 25 group including at least a zinc methyl - methacrylate resin and a zinc dimethyl - methacrylate resin; (c) a curative compound of from 0.25 parts to 3 parts selected from the group including (i) dicumyl peroxide, (ii) derivatives of dicumyl peroxide; 30 (iii) sulfur, and (iv) sulfur donor chemicals; and D. An antidegradant mixture comprising from 0.25 to 2 parts by weight of an antioxidant selected from the group including at least the antioxidants from the respective families of (a) quinolines, 35 (b) substituted para-phenylenediamines (PPD), and (c) hindered bisphenols; and

12. The process of claim 11, wherein the mixing of the polymer recited in A alternatively includes blending of from 80 parts to 90 parts of the highly saturated nitrile, with from 10 parts to 20 parts of a 40 carboxylated nitrile.

13. The process of claim 11, wherein the mixing of the polymer recited in A alternatively includes blending of from 45 parts to 90 parts of the highly saturated nitrile, with from 1 to a maximum of 5 parts of a carboxylated nitrile, and further with from 5 to 50 parts of a nitrile rubber. 45 14. The process of claim 11, wherein the blending of the filler material in B includes selecting the stated amounts of filler from a group including (a) medium processed channel black; and (b) carbon black particles selected from a subgroup consisting of N-110, N-121, N-220, and N- 50 330 as designated by ASTM D - 1765.

15. The process of claim 14, wherein the filler material is modified or further blended to include a blend of said carbon black particles together with from 1 to 15 parts of fumed silica contributing to said overall 15-25 parts by weight of said highly reinforcing material. 55 16. The process of claim 11, wherein said antioxidant is polymerized 1,2 dihydro - 2,2,4 trimethylquinoline (TMQ) antioxidant (TMQ).

13 EP 0 326 394 B1

17. The process of claim 11, wherein said antioxidant is para - phenylenediamine (PPD).

18. The process of claim 11, wherein said antioxidant is known as N-lsopropyl phenyl - p - phenylene - diamine. 5 19. The process of claim 11, wherein the mixing with the polymer recited in A includes using a polymer having a degree of unsaturation ranging between 2.5% and 5%; and further using a curative compound which consists of a sulfur donor N - cyclo - hexyl - 2 - benzothiazole sulfenamide.

io 20. The process of claim 11, wherein the mixing with the polymer recited in A includes using a polymer having a degree of unsaturation ranging between 2.5% and 5%; and further using a curative compound which consists of tetra - methylthiuram disulfide.

21. The process of any one of claims 11-20 in which the polymer material of A includes all grades of is highly saturated nitrile; and in which the selected curative compound of C(c) of claim 11 is dicumyl peroxide.

22. A process for making a compression - molded track pad product which product includes assembly with metal mounting plates in combination with the vulcanizate obtained from any of the compositions 20 defined in claims 1-10, said process including the steps of: A. making a predetermined size preform block of the vulcanizable composition; B. coating the metal mounting plates with a suitable heat - activated adhesive; C. preheating said preform block to about 82° C (180° F); D. preheating said metal mounting plates also to about 82° C (180° F); 25 E. assembling said mounting plates and said preform into a mold which has been preheated to about 165° C (330° F.), which corresponds to a preset temperature of a compression press; F. closing said mold and said compression press, while maintaining the press temperature of about 177°C (350 °F.); G. simultaneously maintaining a minimum pressure of about 13.8bar (200 p.s.i.) within said mold for 30 a period of about 80 minutes; and H. thereafter removing said product from said press and compression mold.

23. A vulcanizate product made by heating and compression molding of the compositions defined in any of claims 1-10 via the use of applicable molds and requisite related product inserts to which the 35 vulcanizate is bonded, said vulcanizate product being of a predetermined size and shape to constitute a particular elastomeric component family member of a group of elastomeric family component members including track pads, road wheels, and bushing members all useable in conjunction with a tank track system;

40 24. A vulcanizable product member formed according to the process of any of claims 11-21, for which said product member may constitute any one of various elastomeric - containing family component members of various selected, respective family groups embodying (a) tank track components including at least track pads, road wheels, and related bushing members all useable with tank tract systems; 45 (b) various elastomeric abutment and stop or limit members repetitively engageable by moving mechanisms; and (c) various at least semi -flexible baffle and skirt family members useable with various air cushion type vehicles; said product member formation utilizing known compression molding equipment and subassembly 50 procedures in conjunction with associated bondable metallic and non - metallic product components, and wherein for at least certain family members said elastomeric composition is suitable preformed as by extruding and shaping into predetermined size blocks which thereafter are respectively preheated and assembled with the respective associatable bondable product components, such as pad - mounting 55 plates, wheel hub members and bushing sleeves, into a requisite shaped preheated mold, and wherein the vulcanizate end product is formed by requisite heating and compression molding procedures.

14 EP 0 326 394 B1

25. The composition of claim 1 wherein said polymer system is selected from the group consisting of: (a) about 100 parts by weight of highly saturated nitrile polymer having a degree of unsaturation ranging between 1% to 5%; (b) a blend of from 80 to 90 parts by weight of highly saturated nitrile polymer having a degree of 5 unsaturation ranging between 1% to 5%, and of from 10 to 20 parts by weight of carboxylated nitrile; and (c) a blending of from 45 to 90 parts of highly saturated nitrile polymer having a degree of unsaturation ranging between 1% to 5%, and of from 1 to a maximum of 5 parts of carboxylated nitrile polymer, and of from 5 to 50 parts of nitrile rubber. 10 26. The process of claim 1 1 , wherein said polymer system is selected from the group consisting of: (a) about 100 parts by weight of highly saturated nitrile polymer having a degree of unsaturation ranging between 1% to 5%; (b) a blend of from 80 to 90 parts by weight of highly saturated nitrile polymer having a degree of is unsaturation ranging between 1% to 5%, and of from 10 to 20 parts by weight of carboxylated nitrile; and (c) a blending of from 45 to 90 parts of highly saturated nitrile polymer having a degree of unsaturation ranging between 1% to 5%, and of from 1 to a maximum of 5 parts of carboxylated nitrile polymer, and of from 5 to 50 parts of nitrile rubber. 20 Claims for the following Contracting States : AT, SE

1. A vulcanizable elastomeric composition, comprising a combination of respective polymer, filler, curing, and antidegradant systems, wherein 25 (A) said polymer system is selected from a group including (a) about 100 parts by weight of highly saturated nitrile polymer; (b) a blend of from 80 to 90 parts by weight of highly saturated nitrile polymer, and of from 10 to 20 parts by weight of carboxylated nitrile; and (c) a blend of from 45 to 90 parts of highly saturated nitrile polymer, and of from 1 to a maximum 30 of 5 parts of carboxylated polymer, and of from 5 to 50 parts of nitrile rubber; and (B) said curing system comprises (a) from 1.5 to 30 parts by weight of a metallic oxide; selected from a group including at least zinc oxide and magnesium oxide; (b) from 25 to 50 parts by weight of a metallic methyl - methacrylate resin selected from a group 35 including at least a zinc methyl - methacrylate resin and a zinc dimethyl - methacrylate resin; (c) a curative compound of from .25 parts to 3 parts selected from the group including (i) dicumyl peroxide, (ii) derivatives of dicumyl peroxide; (iii) sulfur, and 40 (iv) sulfur donor chemicals.

2. The composition of claim 1, wherein said filler system comprises from 15 to 25 parts by weight of a highly reinforcing filler material.

45 3. The composition of claim 2, wherein said filler system is selectable from a group including (a) medium processed channel black; and (b) carbon black particles of the type selected from a subgroup including N-110, N-121, N-220, and N-330 as designated by ASTM D-1765.

50 4. The composition of claim 1, wherein said antidegradant system comprises from 0.25 to 2.0 parts by weight of an antioxidant selected from the group including at least the antioxidants from the respective families of (a) quinolines, (b) substituted para -phenylenediamine (PPD), and 55 (c) hindered bisphenols.

5. A vulcanizable elastomeric composition as claimed in claim 1, wherein said filler system comprises from 15 to 25 parts by weight of a highly reinforcing filler material; and

15 EP 0 326 394 B1

said antidegradant system comprises from 0.25 to 2.0 parts by weight of an antioxidant selected from the group including at least the antioxidants from the respective families of (a) quinolines, (b) substituted para -phenylenediamine (PPD), and 5 (c) hindered bisphenols.

6. The composition of claim 3, wherein said filler system is modified to include a blend of said carbon black particles together with from 1 to 15 parts of fumed silica contributing to said overall 15-25 parts by weight of said highly reinforcing filler. 70 7. The composition of claim 4, wherein said antidegradant system consists of from 0.25 to 2 parts by weight of polymerized 1 ,2 dihydro - 2,2,4 trimethyl - quinoline antioxidant (TMQ).

8. The composition of claim 4, wherein said antidegradant system consists of from 0.25 parts to 2 parts 75 by weight of a substituted paraphenylenediamine (PPD).

9. The composition of claim 4, wherein said antidegradant system comprises a substituted paraphenylenediamine (PPD) which is N-lsopropyl phenyl - p - phenylene - diamine.

20 10. The composition of any of claims 1, 2, 3, 4 and 5 in which said highly saturated nitrile polymer in paragraph A has a degree of unsaturation ranging between 2.5% and 5%; and wherein said curative compound consists of a tetramethyl -thiuram disulfide.

11. The composition of any of claims 1, 2, 3, 4 and 5 which includes highly saturated nitrile rubber having a 25 degree of unsaturation ranging between 1% and 20%, and in which said curative compound consists of dicumyl peroxide.

12. A vulcanizable elastomeric composition as claimed in claim 1, wherein said polymer system consists of about 100 parts by weight of a highly saturated nitrile polymer. 30 13. A process for preparation of a vulcanizable elastomeric composition comprising blending a mixture of A. about 100 parts by weight of highly saturated nitrile polymer; B. from 15 to 25 parts by weight of a highly reinforcing filler, C. a curative mixture comprising 35 (a) from 1 .5 to 30 parts by weight of a metallic oxide selected from a group including at least zinc oxide and magnesium oxide (b) from 25 to 50 parts by weight of a metallic methy - methacrylate resin selected from a group including at least a zinc methyl - methacrylate resin and a zinc dimethyl - methacrylate resin; (c) a curative compound of from 0.25 parts to 3 parts selected from the group including 40 (i) dicumyl peroxide, (ii) derivatives of dicumyl peroxide; (iii) sulfur, and (iv) sulfur donor chemicals; and D. An antidegradant mixture comprising from 0.25 to 2 parts by weight of an antioxidant selected 45 from the group including at least the antioxidants from the respective families of (a) quinolines, (b) substituted para -phenylenediamine (PPD), and (c) hindered bisphenols.

50 14. The process of claim 13, wherein the mixing of the polymer recited in A alternatively includes blending of from 80 parts to 90 parts of the highly saturated nitrile, with from 10 parts to 20 parts of a carboxylated nitrile.

15. The process of claim 13, wherein the mixing of the polymer recited in A alternatively includes blending 55 of from 45 parts to 90 parts of the highly saturated nitrile, with from 1 to a maximum of 5 parts of a carboyxlated nitrile, and further with from 5 to 50 parts of a nitrile rubber.

16 EP 0 326 394 B1

16. The process of claim 13, wherein the blending of the filler material in B includes selecting the stated amounts of filler from a group including (a) medium processed channel black; and (b) carbon black particles of the type selected from a subgroup including 5 N - 1 1 0, N - 1 21 , N - 220, and N - 330 as designated by ASTM D - 1 765.

17. The process of claim 16, wherein the filler material is modified or further blended to include a blend of said carbon black particles together with from 1 to 15 parts of funed silica contributing to said overall 15-25 parts by weight of said highly reinforcing material. 10 18. The process of claim 13, wherein said antioxidant is polymerized 1,2 dihydro - 2,2,4 trimethylquinoline antioxidant (TMQ).

19. The process of claim 13, wherein said antioxidant is para - phenylenediamine (PPD). 15 20. The process of claim 13, wherein said antioxidant is known as N-lsopropyl phenyl -p- phenylenediamine.

21. The process of claim 13, wherein the mixing with the polymer recited in A includes using a polymer 20 having a degree of unsaturation ranging between 2.5% and 5%; and further using a curative compound which consists of a sulfur donor N - cyclo - hexyl - 2 - benzothiazole sulfenamide.

22. The process of claim 13, wherein the mixing with the polymer recited in A includes using a polymer having a degree of unsaturation ranging between 2.5% and 5%; and further using a curative compound 25 which consists of tetra - methyl - thiuram disulfide.

23. The process of any of claims 13-22 in which the polymer material of A includes all grades of highly saturated nitrile; and in which the selected curative compound of C(c) of claim 13 is dicumyl peroxide.

30 24. A process for making a compression - molded track pad product which product includes assembly with metal - mounting plates in combination with the vulcanizate obtained from any of the compositions defined in claims 1-12, said process including the steps of: A. making a predetermined size preform block of the vulcanizable composition; B. coating the metal mounting plates with a suitable heat - activated adhesive; 35 C. preheating said preform block to about 82° C (180° F); D. preheating said metal mounting plates also to about (180° F) 82° C; E. assembling said mounting plates and said preform into a mold which has been preheated to about 165° C (330° F.), which corresponds to a preset temperature of a compression press; F. closing said mold and said compression press, while maintaining the press temperature of about 40 1 77°C (350 °F.); G. simultaneously maintaining a minimum pressure of about 13.8bar (200 p.s.i.) within said mold for a period of about 80 minutes; and H. thereafter removing said product from said press and compression mold.

45 25. A vulcanizate product made by heating and compression molding of the compositions defined in any of claims 1-12 via the use of applicable molds and requisite related product inserts to which the vulcanizate is bonded, said vulcanizate product being of a predetermined size and shape to constitute a particular elastomeric component family member of a group of elastomeric family component members including track pads, road wheels, and bushing members all useable in conjunction with a tank track 50 system.

26. A vulcanizable product member formed according to the process of any of claims 13-23, for which said product member may constitute any one of various elastomeric -containing family component members of various selected, respective family groups embodying 55 (a) tank track components including at least track pads, road wheels, and related bushing members all useable with tank track systems; (b) various elastomeric abutment and stop or limit members repetitively engageable by moving mechanisms; and

17 EP 0 326 394 B1

(c) various at least semi -flexible baffle and skirt family members useable with various air cushion type vehicles; said product member formation utilizing known compression molding equipment and subassembly procedures in conjunction with associated bondable metallic and non - metallic product components, 5 and wherein for at least certain family members said elastomeric composition is suitable preformed as by extruding and shaping into predetermined size blocks which thereafter are respectively preheated and assembled with the respective associatable bondable product components, such as pad - mounting plates, wheel hub members and bushing sleeves, into a requisite shaped preheated mold, and io wherein the vulcanizate end product is formed by requisite heating and compression molding procedures.

27. The composition of Claim 1 wherein said polymer system is selected from the group consisting of: (a) about 100 parts by weight of highly saturated nitrile polymer having a degree of unsaturation is ranging between 1% to 5%; (b) a blend of from 80 to 90 parts by weight of highly saturated nitrile polymer having a degree of unsaturation ranging between 1% to 5%, and of from 10 to 20 parts by weight of carboxylated nitrile; and (c) a blend of from 45 to 90 parts of highly saturated nitrile polymer having a degree of unsaturation 20 ranging between 1% to 5%, and of from 1 to a maximum of 5 parts of carboxylated nitrile polymer, and of from 5 to 50 parts of nitrile rubber.

28. The process of Claim 13 wherein said polymer system is selected from the group consisting of: (a) about 100 parts by weight of highly saturated nitrile polymer having a degree of unsaturation 25 ranging between 1% to 5%; (b) a blend of from 80 to 90 parts by weight of highly saturated nitrile polymer having a degree of unsaturation ranging between 1% to 5%, and of from 10 to 20 parts by weight of carboxylated nitrile; and (c) a blend of from 45 to 90 parts of highly saturated nitrile polymer having a degree of unsaturation 30 ranging between 1% to 5%, of from 1 to a maximum of 5 parts of carboxylated nitrile polymer, and of from 5 to 50 parts of nitrile rubber.

Patentanspruche Patentanspruche fur folgende Vertragsstaaten : DE, FR, GB 35 1. Vulkanisierbare elastomerische Zusammensetzung, bestehend aus einer einzigartigen Kombination von jeweiligen Polymer-, Fullstoff-, Vulkanisations - und Antiabbausystemen, wobei A) das Polymersystem aus einer Gruppe ausgewahlt ist, die umfaBt a) etwa 100 Gewichtsteile hochgesattigten Nitrilpolymer, 40 b) ein Gemisch aus 80 bis 90 Gewichtsteilen des hochgesattigten Nitrilpolymers und 10 bis 20 Gewichtsteilen carboxyliertem Nitril, und c) ein Gemisch aus 45 bis 90 Teilen des hochgesattigten Nitrilpolymers und 1 bis maximal 5 Teilen carboxyliertem Polymer sowie 5 bis 50 Teilen Nitrilgummi, und B) das Vulkanisationssystem besteht aus 45 a) 1,5 bis 30 Gewichtsteilen eines Metalloxids, das aus einer Gruppe ausgewahlt ist, die mindestens Zinkoxid und Magnesiumoxid enthalt b) 25 bis 50 Gewichtsteilen eines Metall - Methylmethacrylatharzes, das aus einer Gruppe ausgewahlt ist, das mindestens aus einem Zink - Methylmethacrylatharz und einem Zink- Dimethylmethacrylatharz besteht, 50 c) einer Vulkanisationsverbindung aus 0,25 bis 3 Teilen, die aus der Gruppe ausgewahlt sind, die umfaBt i) Dicumylperoxid ii) Derivate von Dicumylperoxid, iii) Schwefel, und 55 iv) Schwefeldonatorchemikalien, C) das Fullstoffsystem 15 bis 25 Gewichtsteile eines hochverstarkenden Fullstoffmaterials aufweist, wobei das Fullstoffmaterial aus der Gruppe auswahlbar ist, die umfaBt a) mittelverarbeiteter KanalruB, und

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b) RuBteilchen des Typs, der aus einer Untergruppe ausgewahlt ist, der N-110, N-121, N-220 und N-330 nach den Bezeichnungen gemaB ASTM D-1765 enthalt.

2. Zusammensetzung nach Anspruch 1, wobei das Antiabbausystem 0,25 bis 2,0 Gewichtsteile eines 5 Antioxidationsmittels aufweist, das aus der Gruppe ausgewahlt ist, die mindestens die Antioxidations - mittel aus den jeweiligen Familien der a) Chinoline, b) substituierten Para- Phenylendiamine (PPD), und c) gestorten Bisphenole enthalt. 10 3. Vulkanisierbare elastomerische Zusammensetzung, enthaltend eine Kombination aus jeweiligen Polymer-, Fullstoff-, Vulkanisations - und Antiabbausystemen, wobei A) das Polymersystem aus einer Gruppe ausgewahlt ist, die enthalt a) etwa 100 Gewichtsteile hochgesattigten Nitrilpolymer, is b) ein Gemisch aus 80 bis 90 Gewichtsteilen hochgesattigtem Nitrilpolymer und 10 bis 20 Gewichtsteilen carboxyliertem Nitril, und c) ein Gemisch aus 45 bis 90 Teilen hochgesattigtem Nitrilpolymer, 1 bis maximal 5 Teilen carboxyliertem Nitrilpolymer, und 5 bis 50 Teilen Nitrilgummi, B) das Fullstoffsystem 15 bis 25 Gewichtsteile eines hochverstarkenden Fullstoffmaterials aufweist, 20 C) das Vulkanisationssystem aufweist a) 1,5 bis 30 Gewichtsteile eines Metalloxids, das aus einer Gruppe ausgewahlt ist, die mindestens Zinkoxid und Magnesiumoxid enthalt, b) 25 bis 50 Gewichtsteile eines Metall - Methylmethacrylatharzes, das aus einer Gruppe ausge - wahlt ist, die mindestens ein Zink- Methylmethacrylatharz und ein Zink- Dimethylmethacrylat- 25 harz enthalt, c) eine Vulkanisationsverbindung aus 0,25 bis 3 Teilen, die aus der Gruppe ausgewahlt sind, die besteht aus i) Dicumylperoxid ii) Derivaten von Dicumylperoxid 30 iii) Schwefel, und iv) Schwefeldonatorchemikalien, und D) das Antiabbausystem 0,25 bis 2,0 Gewichtsteile eines Antioxidationsmittels aufweist, das aus der Gruppe ausgewahlt ist, die aus Antioxidationsmitteln aus den jeweiligen Familien der a) Chinoline, 35 b) substituierten Para- Phenylendiamine (PPD), und c) gestorten Bisphenolen besteht.

4. Zusammensetzung nach Anspruch 1, wobei das Fullstoffsystem so modifiziert ist, dal3 es ein Gemisch aus den Kohlenstoffteilchen zusammen mit 1 bis 15 Teilen gerauchertem Siliziumoxid enthalt, das zu 40 den insgesamt 15 bis 25 Gewichtsteilen des hochverstarkenden Fullstoffs beitragt.

5. Zusammensetzung nach Anspruch 2, wobei das Antiabbausystem aus 0,25 bis 2 Gewichtsteilen polymerisiertem 1, 2 -Dihydro- 2,2,4 -Trimethyl- Chinoline - Antioxidationsmittel (TMQ) besteht.

45 6. Zusammensetzung nach Anspruch 2, wobei das Antiabbausystem aus 0,25 bis 2 Gewichtsteilen eines substituierten Para- Phenylendiamins (PPD) besteht.

7. Zusammensetzung nach Anspruch 2, wobei das Antiabbausystem ein substituiertes Para- Phenylen - diamin (PPD) aufweist, das N - Isopropylphenyl - p - Phenylendiamin ist. 50 8. Zusammensetzung nach einem der Anspruche 1 , 2 oder 3, wobei der hochgesattigte Nitrilpolymer nach Absatz A einen Ungesattigtheitsgrad im Bereich zwischen 2,5 % und 5 % hat, und wobei die Vulkanisationsverbindung aus einem Tetra- Methylthiuram - Disulfid besteht.

55 9. Zusammensetzung nach einem der Anspruche 1, 2 oder 3, die hochgesattigten Nitrilgummi enthalt, der einen Ungesattigtheitsgrad im Bereich zwischen 1 % und 20 % hat und bei welchem die Vulkanisa- tionsverbindung aus Dicumylperoxid besteht.

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10. Vulkanisierbare elastomere Zusammensetzung nach Anspruch 1, wobei das Polymersystem aus etwa 100 Gewichtsteilen eines hochgesattigten Nitrilpolymers besteht.

11. Verfahren zur Zubereitung einer vulkanisierbaren elastomerischen Zusammensetzung, mit Herstellung 5 eines Gemisches aus A) etwa 100 Gewichtsteilen hochgesattigtem Nitrilpolymer, B) 15 bis 25 Gewichtsteilen eines hochverstarkenden Fullstoffs, C) einem Vulkanisationsgemisch, das enthalt a) 1 ,5 bis 30 Gewichtsteile eines Metalloxids, das aus der Gruppe ausgewahlt ist, die mindestens io Zinkoxid und Magnesiumoxid enthalt, b) 20 bis 50 Gewichtsteile eines Metall - Methylmethacrylatharzes, das aus der Gruppe ausge - wahlt ist, die mindestens ein Zink - Methylmethacrylatharz und ein Zink- Dimethylmethacrylat- harz enthalt, c) eine Vulkanisationsverbindung aus 0,25 bis 3 Teilen, die aus der Gruppe ausgewahlt sind, die 15 enthalt i) Dicumylperoxid, ii) Derivate von Dicumylperoxid iii) Schwefel, und iv) Schwefeldonatorchemikalien, und 20 D) einem Antiabbaugemisch, das 0,25 bis 2 Gewichtsteile eines Antioxidationsmittels aufweist, das aus der Gruppe ausgewahlt ist, die mindestens die Antioxidationsmittel aus den jeweiligen Familien der a) Chinoline, b) substituierten Para- Phenylendiamine (PPD), und 25 c) gestorten Bisphenole enthalt.

12. Verfahren nach Anspruch 11, wobei das Mischen des unter A) genannten Polymers alternativ das Mischen aus 80 bis 90 Teilen des hochgesattigten Nitrils mit 10 bis 20 Teilen carboxyliertem Nitril umfaBt. 30 13. Verfahren nach Anspruch 11, wobei das Mischen des unter A) genannten Polymers als alternativ das Mischen von 45 bis 90 Teilen des hochgesattigtem Nitrils mit 1 bis maximal 5 Teilen eines carboxylierten Nitrils und auBerdem mit 5 bis 50 Teilen eines Nitrilgummis umfaBt.

35 14. Verfahren nach Anspruch 11, wobei das Mischen des Fullstoffmaterials nach B) das Auswahlen der angegebenen Fullstoffmengen aus einer Gruppe umfaBt, die enthalt a) mittelverarbeiteten KanalruB, und b) RuBteilchen, die aus einer Untergruppe ausgewahlt sind, die aus N-110, N-121, N-220 und N-330 nach den Bezeichnungen ASTM D-1765 besteht. 40 15. Verfahren nach Anspruch 14, wobei das Fullstoffmaterial so modifiziert oder weiter verschnitten ist, dal3 dies ein Gemisch aus den Kohlenstoffteilchen zusammen mit 1 bis 15 Teilen gerauchertem Silizium- oxid enthalt, das zu den insgesamt 15 bis 25 Gewichtsteilen des hochverstarkenden Materials beitragt.

45 16. Verfahren nach Anspruch 11, wobei das Antioxidationsmittel polymerisiertes 1,2-Dihydro-2,2,4- Trimethyl - Chinolin -Antioxidationsmittel (TMQ) ist.

17. Verfahren nach Anspruch 11, wobei das Antioxidationsmittel Para- Phenylendiamin (PPD) ist.

50 18. Verfahren nach Anspruch 11, wobei das Antioxidationsmittel als N - Isopropylphenyl - p - Phenylendi - amin bekannt ist.

19. Verfahren nach Anspruch 11, wobei das Mischen mit dem unter A) genannten Polymer die Verwendung eines Polymers mit einem Ungesattigtheitsgrad im Bereich von 2,5 % und 5 % und auBerdem das 55 Verwenden einer Vulkanisationsverbindung umfaBt, die aus einem Schwefeldonator - N - Cyclohexyl - 2 - Benzothiazol - Sulfenamid besteht.

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20. Verfahren nach Anspruch 1 1 , wobei das Mischen mit dem unter A) genannten Polymer die Verwendung eines Polymers mit einem Ungesattigtheitsgrad im Bereich zwischen 2,5 % und 5 % und auBerdem die Verwendung einer Vulkanisationsverbindung umfaBt, die aus Tetra- Methylthiuram - Disulfid besteht.

5 21. Verfahren nach einem der Anspruche 11 bis 20, wobei das Polymermaterial nach A) alle Sorten hochgesattigtes Nitril enthalt, und wobei die gewahlte Vulkanisationsverbindung nach C)c) gemaB Anspruch 1 1 Dicumyl peroxid ist.

22. Verfahren zur Herstellung eines formgepreBten Raupengliedprodukts, das einen Zusammenbau mit io metallenen Montageplatten in Kombination mit dem aus einer der in den Anspruchen 1 bis 10 definierten Zusammensetzungen erhaltenen Vulkanisat aufweist, wobei das Verfahren die Schritte aufweist: a) Herstellen eines Vorformblocks vorgegebener GroBe aus der vulkanisierbaren Zusammensetzung, B) Beschichten der metallenen Montageplatten mit einem geeigneten warmeaktivierten Klebstoff, is C) Vorheizen des Vorformblocks auf etwa 82 ° C(180° F), B) Vorheizen der metallenen Montageplatten ebenfalls auf etwa 82° C (180° F), E) Zusammensetzen der Montageplatten und des Vorformblocks in einer Form, die auf etwa 165° C (330° F) vorgeheizt worden ist, was einer Voreinstelltemperatur einer Druckpresse entspricht, F) SchlieBen der Form und der Druckpresse, wahrend die PreBtemperatur von etwa 177° C (350° 20 F) aufrechterhalten wird, G) Gleichzeitiges Aufrechterhalten eines Minimaldrucks von etwa 13,8 bar (200 p.s.i.) innerhalb der Form wahrend einer Dauer von etwa 80 Minuten, und H) AnschlieBendes Herausnehmen des Produkts aus der Druckpresse und der Form.

25 23. Vulkanisatprodukt, das durch Erwarmen und Formpressen der in einem der Anspruche 1 bis 10 definierten Zusammensetzungen unter Verwendung anwendbarer Formen und bedarfsgemaBer Pro- dukteinsetze, mit welchem das Vulkanisat verbunden wird, hergestellt wird, wobei das Vulkanisatpro- dukt von vorgegebener GroBe und Form ist, urn ein bestimmtes elastomerisches Bauteilfamilienmitglied einer Gruppe von elastomerischen Bauteilfamiliengmitgliedern darzustellen, zu denen Raupenglieder, 30 StraBenrader und Buchsen gehoren, die alle im Zusammenhang mit einem Panzerkettensystem einsetzbar sind.

24. Vulkanisierbares Produkt, das nach dem Verfahren nach einem der Anspruche 1 1 bis 21 hergestellt ist, wobei das Produkt irgendeines von verschiedenen elastomerhaltigen Bauteilfamilienmitgliedern von 35 verschiedenden ausgewahlten jeweiligen Familiengruppen darstellen kann, die umfassen a) Panzerkettenbauteile, die mindestens Raupenglieder, StraBenrader und damit zusammenhan - gende Buchsen enthalten, die alle bei Panzerkettensystemen einsetzbar sind, b) verschiedene elastomerische Anschlag- und Stopper- oder Begrenzerbauteile, die wiederholt durch sich bewegende Mechanismen anschlagbar sind, und 40 c) verschiedene mindestens halbflexible Mitglieder der Familie Ablenkplatten und Schurzen, die bei verschiedenen Luftkissenfahrzeugen einsetzbar sind, wobei die Produktherstellung unter Verwendung bekannter PreBformausrustung und Baugruppenver- fahren im Zusammenhang mit zugeordneten verbindbaren metallischen und nichtmetallischen Pro- duktkomponenten erfolgt, und 45 wobei fur mindestens gewisse Familienmitglieder die elastomerische Zusammensetzung beispielsweise durch Extrudieren und Formen in Blocke vorgegebener GroBe geeignet vorgeformt wird, welche anschlieBend jeweils vorerwarmt und mit den betreffenden zuordnungsfahigen verbindbaren Produkt - komponenten wie beispielsweise Gliedmontageplatten, Radnabenbauteile und Lagerhulsen in einer bedarfsgerecht gestalteten vorgeheizten Form zusammengesetzt werden, 50 wobei das Vulkanisat- Endprodukt durch bedarfsweise Heiz- und FormpreBverfahren hergestellt wird.

25. Zusammensetzung nach Anspruch 1, wobei das Polymersystem aus der Gruppe ausgewahlt ist, das besteht aus: a) etwa 100 Gewichtsteilen hochgesattigtem Nitrilpolymer mit einem Ungesattigtheitsgrad im Bereich 55 zwischen 1 % und 5 %, b) einem Gemisch aus 80 bis 90 Gewichtsteilen hochgesattigtem Nitrilpolymer mit einem Ungesat- tigtheitsgrad im Bereich zwischen 1 % und 5 % und aus 10 bis 20 Gewichtsteilen carboxyliertem Nitril, und

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c) einem Gemisch aus 45 bis 90 Teilen hochgesattigtem Nitrilpolymer mit einem Ungesattigtheits - grad im Bereich zwischen 1 % und 5 % und 1 bis maximal 5 Teilen carboxyliertem Nitrilpolymer sowie 5 bis 50 Teilen Nitrilgummi.

5 26. Verfahren nach Anspruch 1 , wobei das Polymersystem aus der Gruppe ausgewahlt ist, die besteht aus: a) etwa 100 Gewichtsteilen hochgesattigtem Nitrilpolymer mit einem Ungesattigtheitsgrad im Bereich zwischen 1 % und 5 %, b) einem Gemisch aus 80 bis 90 Gewichtsteilen hochgesattigtem Nitrilpolymer mit einem Ungesat- tigtheitsgrad zwischen 1 % und 5 % und 10 bis 20 Gewichtsteilen carboxyliertem Nitril, und io c) einem Gemisch aus 45 bis 90 Teilen hochgesattigtem Nitrilpolymer mit einem Ungesattigtheits - grad im Bereich zwischen 1 % und 5 % und 1 bis maximal 5 Teilen carboxyliertem Nitrilpolymer, sowie 5 bis 50 Teilen Nitrilgummi.

Patentanspruche fur folgende Vertragsstaaten : AT, SE 15 1. Vulkanisierbare elastomerische Zusammensetzung, enthaltend eine Kombination aus jeweiligen Polymer-, Fullstoff-, Vulkanisations - und Antiabbausystemen, wobei A) das Polymersystem aus einer Gruppe ausgewahlt ist, die umfaBt: a) etwa 100 Gewichtsteile hochgesattigten Nitrilpolymer, 20 b) eine Mischung aus 80 bis 90 Gewichtsteilen hochgesattigtem Nitrilpolymer und aus 10 bis 20 Gewichtsteilen carboxyliertem Nitril, und c) eine Mischung aus 45 bis 90 Teilen hochgesattigtem Nitrilpolymer, und aus 1 bis maximal 5 Teilen carboxyliertem Polymer, und aus 5 bis 50 Teilen Nitrilgummi, und B) das Aushartesystem aufweist: 25 a) 1,5 bis 30 Gewichtsteile eines Metalloxids, das aus einer Gruppe ausgewahlt ist, die mindestens Zinkoxid und Magnesiumoxid enthalt, b) 25 bis 50 Gewichtsteile eines Metall - Metylmethacrylatharzes, das aus einer Gruppe ausge - wahlt ist, die mindestens ein Zink- Methylmethacrylatharz und ein Zink- Dimethylmethacrylat- harz enthalt, 30 C) eine Vulkanisationsverbindung aus 0,25 bis 3 Teilen aus der Gruppe, die umfaBt i) Dicumylperoxid, ii) Derivate von Dicumylperoxid, iii) Schwefel, und iv) Schwefeldonatorchemikalien. 35 2. Zusammensetzung nach Anspruch 1, wobei das Fullstoffsystem 15 bis 25 Gewichtsteile eine hochverstarkenden Fullstoffmaterials enthalt.

3. Zusammensetzung nach Anspruch 2, wobei das Fullstoffsystem aus einer Gruppe auswahlbar ist, die 40 umfaBt a) mittelverarbeiteten KanalruB, und b) RuBteilchen des Typs, der aus einer Untergruppe ausgewahlt ist, die N-110, N-121, N-220 und N-330 gemaB den Bezeichnungen nach ASTM D-1765 enthalt.

45 4. Zusammensetzung nach Anspruch 1 , wobei das Antiabbausystem 0,25 bis 2,0 Gewichtsprozent eines Antioxidationsmittels aufweist, das aus der Gruppe ausgewahlt ist, die mindestens die Antioxidations - mittel aus den jeweiligen Familien der a) Chinoline, b) substituierten Para- Phenylendiamine (PPD), und 50 c) gestorten Bisphenole umfaBt.

5. Vulkanisierbare elastomerische Zusammensetzung nach Anspruch 1, wobei des Fullstoffsystem 15 bis 25 Gewichtsprozent eines hochverstarkenden Fullstoffmaterials aufweist, und das Antiabbausystem 0,25 bis 2,0 Gewichtsprozent eines Antioxidationsmittels aufweist, das aus der 55 Gruppe ausgewahlt ist, die mindestens die Antioxidationsmittel aus den jeweiligen Familien der a) Chinoline, b) substituierten Para- Phenylendiamine (PPD), und c) gestorten Bisphenole umfaBt.

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6. Zusammensetzung nach Anspruch 3, wobei das Fullstoffsystem so modifiziert ist, daB es eine Mischung der RuBteilchen zusammen mit 1 bis 15 Teilen gerauchertem Siliciumoxid enthalt, das zu den insgesamt 15 bis 25 Gewichtsteilen des hochverstarkenden Fullstoffs beitragt.

5 7. Zusammensetzung nach Anspruch 4, wobei das Antiabbausystem aus 0,25 bis 2 Gewichtsteilen polymerisiertem 1, 2 -Dihydro- 2,2,4 -Trimethyl-Chinolin- Antioxidationsmittel (TMQ) besteht.

8. Zusammensetzung nach Anspruch 4, wobei das Antiabbausystem aus 0,25 bis 2 Gewichtsteilen eines substituierten Para- Phenylendiamins (PPD) besteht. 10 9. Zusammensetzung nach Anspruch 4, wobei das Antiabbausystem ein substituiertes Para- Phenylen - diamin (PPD) aufweist, das N - Isopropylphenyl - p - phenylendiamin ist.

10. Zusammensetzung nach einem der Anspruche 1, 2, 3, 4 und 5, in welcher der hochgesattigte is Nitrilpolymer nach Absatz A einen Ungesattigtheitsgrad im Bereich zwischen 2,5 % und 5 % hat, und wobei die Vulkanisierungsverbindung aus einem Tetra- Methylthiruamdisulfid besteht.

11. Zusammensetzung nach einem der Anspruche 1, 2, 3 , 4 und 5, welche hochgesattigten Nitrilgummi mit einem Ungesattigtheitsgrad im Bereich zwischen 1 % und 20 % enthalt, und wobei die Vulkanisie - 20 rungsverbindung aus Dicumylperoxid besteht.

12. Vulkanisierbare elastomerische Zusammensetzung nach Anspruch 1, wobei das Polymersystem aus etwa 100 Gewichtsteilen eines hochgesattigten Nitrilpolymers besteht.

25 13. Verfahren zur Zubereitung einer vulkanisierbaren elastomerischen Zusammensetzung, welches das Herstellen eines Gemisches umfaBt aus A) etwa 100 Geweichtsteilen eines hochgesattigten Nitrilpolymers, B) 15 bis 25 Gewichtsteilen eines hochverstarkenden Fullstoffs, C) einem Vulkanisierungsgemisch, das besteht aus 30 a) 1,5 bis 30 Gewichtsteilen eines Metalloxids, das aus einer Gruppe ausgewahlt ist, die mindestens Zinkoxid und Magnesiumoxid enthalt, b) 25 bis 50 Gewichtsteilen eines Metall - Methylmethacrylatharzes, das aus einer Gruppe ausgewahlt ist, das mindestens ein Zink- Methylmethacrylatharz und ein Zink- Dimethylmetha- crylatharz enthalt, 35 c) einer Vulkanisierungsverbindung aus 0,25 bis 3 Teilen, die aus der Gruppe ausgewahlt sind, die umfaBt i) Dicumylperoxid ii) Derivate von Dicumylperoxid, iii) Schwefel, und 40 iv) Schwefeldonatorchemikalien, und D) einem Antiabbaugemisch, bestehend aus 0,25 bis 2 Gewichtsteilen eines Antioxidationsmittels, das aus der Gruppe ausgewahlt ist, das mindestens die Antioxidationsmittel aus den jeweiligen Familien der a) Chinoline, 45 b) substituierten Para- Phenylendiamine (PPD), und c) gestorten Bisphenole enthalt.

14. Verfahren nach Anspruch 13, wobei das Mischen des unter A) genannten Polymers alternativ das Mischen von 80 bis 90 Teilen des hochgesattigten Nitrils mit 10 bis 20 Teilen eines carboxylierten 50 Nitrils umfaBt.

15. Verfahren nach Anspruch 13, wobei das Mischen des unter A) genannten Polymers alternativ das Mischen von 45 bis 90 Teilen des hochgesattigten Nitrils mit 1 bis maximal 5 Teilen eines carboxylierten Nitrils und auBerdem mit 5 bis 50 Teilen eines Nitrilgummis umfaBt. 55 16. Verfahren nach Anspruch 13, wobei das Mischen des Fullstoffmaterials unter B) das Auswahlen der angegebenen Fullstoffmengen aus einer Gruppe umfaBt, die enthalt a) mittelverarbeiteten KanalruB, und

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b) RuBteilchen des Typs, der aus einer Untergruppe ausgewahlt ist, die N-110, N-121, N-220, N-330 nach den Bezeichnungen nach ASTM D-1765 enthalt.

17. Verfahren nach Anspruch 16, wobei das Fullstoffmaterial so modifiziert oder weiterverschnitten wird, 5 daB es eine Mischung der genannten RuBteilchen zusammen mit 1 bis 15 Teilen gerauchertem Siliziumoxid enthalt, das zu den insgesamt 15 bis 25 Gewichtsteilen des hochverstarkenden Materials beitragt.

18. Verfahren nach Anspruch 13, wobei das Antioxidationsmittel polymerisiertes 1,2-Dihydro-2,2,4- io Trimethylchinolin -Antioxidationsmittel (TMQ) ist.

19. Verfahren nach Anspruch 13, wobei das Antioxidationsmittel Para- Phenylendiamin (PPD) ist.

20. Verfahren nach Anspruch 13, wobei das Antioxidationsmittel als N - Isopropylphenyl - p - Phenylendi - is amin bekannt ist.

21. Verfahren nach Anspruch 13, wobei das Mischen mit dem unter A) genannten Polymer die Verwendung eines Polymers umfaBt, der einen Ungesattigtheitsgrad im Bereich zwischen 2,5 % und 5 % hat, und auBerdem das Verwenden einer Vulkanisationsverbindung umfaBt, die aus einem Schwefeldonator - N - 20 Cyclohexyl - 2 - Benzothiazol - Sulfenamid besteht.

22. Verfahren nach Anspruch 13, wobei das Mischen des unter A) genannten Polymers das Verwenden eines Polymers mit einem Ungesattigtheitsgrad im Bereich zwischen 2,5 % und 5 % und auBerdem die Verwendung einer Vulkanisierungsverbindung umfaBt, die aus Tetra- Methylthiuram - Disulfid besteht. 25 23. Verfahren nach einem der Anspruche 13 bis 22, bei welchem das Polymermaterial nach A) alle Sorten hochgesattigten Nitrils enthalt, und bei welchem die ausgewahlte Vulkanisierungsverbindung nach C)c) gemaB Anspruch 13 Dicumylperoxid ist..

30 24. Verfahren zum Herstellen eines formgepreBten Raupengliedprodukts, das einen Verbund mit metalle - nen Montageplatten in Verbindung mit dem aus einer der Zusammensetzungen nach den Anspruchen 1 bis 12 erhaltenen Vulkanisat umfaBt, wobei das Verfahren die Schritte aufweist: a) Herstellen eines Vorformblocks aus der vulkanisierbaren Zusammensetzung mit vorgegebener GroBe, 35 b) Beschichten der metallenen Montageplatten mit einem geeigneten warmeaktivierten Klebstoff, c) Vorheizen des Vorformblocks auf etwa 82° C (180° F), d) Vorheizen der metallenen Montageplatten ebenfalls auf etwa 82° C (180° F), e) Zusammensetzen der Montageplatten und des Vorformblocks in einer Form, die auf etwa 165° C (330° F) vorgeheizt worden ist, was einer Voreinstelltemperatur einer Druckpresse entspricht, 40 f) SchlieBen der Form und der Druckpresse, wahrend die Presstemperatur von etwa 177° C (350° F) aufrechterhalten wird, g) gleichzeitiges Aufrechterhalten eines Minimaldrucks von etwa 13,8 bar (200 p.s.i.) innerhalb der Form wahrend einer Dauer von etwa 8 Minuten, und h) anschlieBendes Herausnehmen des Produkts aus der Druckpresse und der Form. 45 25. Vulkanisatprodukt, das durch Erwarmen und Formpressen der Zusammensetzungen nach einem der Anspruche 1 bis 12 unter Verwendung anwendbarer Formen und bedarfsbezogener Produkteinsatze, an welche das Vulkanisat gebunden ist, hergestellt ist, wobei das Vulkanisatprodukt von vorgegebener GroBe und Form ist, urn ein bestimmtes elastomerisches Bauteilfamilienmitglied aus einer Gruppe von 50 elastomerischen Bauteilfamilienmitgliedern darzustellen, die Raupenglieder, StraBenrader und Buchsen umfassen, die alle im Zusammenhang mit einem Panzerkettensystem einsetzbar sind.

26. Vulkanisierbares Produkt, das gemaB dem Verfahren nach einem der Anspruche 13 bis 23 hergestellt ist, wobei das Produkt irgendeines von elastomerhaltigen Bauteilfamilienmitgliedern von verschiedenen 55 ausgewahlten Familiengruppen bilden kann, die umfassen a) Panzerkettenbauteile, die mindestens Raupenglieder, StraBenrader und entsprechende Buchsen enthalten, die alle bei Panzerkettensystemen einsetzbar sind,

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b) verschiedene elastomerische Anschlag-, Stopper- oder Begrenzungsbauteile, die durch sich bewegende Mechanismen wiederholt anschlagbar sind, und c) verschiedene mindestens halbflexible Mitglieder der Familie Ablenkplatten und Schurzen, die bei verschiedenen Luftkissenfahrzeugen einsetzbar sind, 5 wobei die Produktherstellung die Verwendung bekannter FormpreBausrustung und Untergruppenver- fahren in Verbindung mit zugeordneten verbindungsfahigen metallischen und nichtmetallischen Pro- duktkomponenten umfaBt, und wobei fur mindestens gewisse Familienmitglieder die elastomerische Zusammensetzung beispielsweise durch Extrudieren und Formen in Blocke vorgegebener GroBe geeignet vorgeformt ist, die anschlie- io Bend entsprechend vorgeheizt und mit den betreffenden zuordnungsfahigen verbindbaren Produkt - komponenten wie beispielsweise Gliedmontageplatten, Radnabenbauteile und Lagerhulsen in einer bedarfsweise gestalteten vorgeheizten Form zusammengesetzt wird, und wobei das Vulkanisat- Endprodukt durch bedarfweise Heiz- und PreBformverfahren hergestellt wird.

75 27. Zusammensetzung nach Anspruch 1, wobei das Polymersystem aus der Gruppe ausgewahlt ist, die besteht aus: a) etwa 100 Gewichtsteilen hochgesattigtem Nitrilpolymer mit einem Ungesattigtheitsgrad im Bereich zwischen 1 % und 5 %, b) einem Gemisch aus 80 bis 90 Gewichtsteilen hochgesattigtem Nitrilpolymer mit einem Ungesat- 20 tigtheitsgrad im Bereich von 1 % bis 5 % und aus 10 bis 20 Gewichtsteilen carboxyliertem Nitril, und c) einem Gemisch von 45 bis 90 Teilen hochgesattigtem Nitrilpolymer mit einem Ungesattigtheits - grad im Bereich zwischen 1 % und 5 %, 1 bis maximal 5 Teilen carboxyliertem Nitrilpoymer, und 5 bis 50 Teilen Nitrilgummi. 25 28. Verfahren nach Anspruch 13, wobei das Polymersystem aus der Gruppe ausgewahlt ist, die besteht aus: a) etwa 100 Gewichtsteilen hochgesattigtem Nitrilpolymer mit einem Ungesattigtheitsgrad im Bereich von 1 % bis 5 %, 30 b) einem Gemisch aus 80 bis 90 Gewichtsteilen hochgesattigtem Nitrilpolymer mit einem Ungesat- tigtheitsgrad im Bereich zwischen 1 % und 5 % und 10 bis 20 Gewichtsteilen carboxyliertem Nitril, und c) einem Gemisch aus 45 bis 90 Teilen hochgesattigtem Nitrilpolymer mit einem Ungesattigtheits - grad im Bereich zwischen 1 % und 5 %, 1 bis maximal 5 Teilen carboxyliertem Nitrilpolymer, und 5 35 bis 50 Teilen Nitrilgummi.

Revendicatlons Revendicatlons pour I'Etats contractants suivants : DE, FR, GB

40 1. Composition elastomere pouvant etre vulcanisee, comprenant une combinaison unique d'un agent formant polymere, d'un agent formant charge de remplissage, d'un agent de prise et d'un agent antidegradant correspondants, caracterisee en ce que: A. ledit agent polymere est choisi dans un groupe comprenant (a) environ 100 parties par poids de polymere nitrile fortement sature; 45 (b) un melange de 80 a 90 parties par poids dudit polymere nitrile fortement sature et de 10 a 20 parties par poids de nitrile carboxyle; et (c) un melange de 45 a 90 parties dudit polymere nitrile fortement sature, et de 1 a 5 parties au maximum de polymere carboxyle, et de 5 a 50 parties de caoutchouc nitrile; et B. ledit agent de prise comprend 50 (a) de 1,5 a 30 parties par poids d'un oxyde de metal choisi dans un groupe comprenant au moins de I'oxyde de zinc et de I'oxyde de magnesium; (b) de 25 a 50 parties par poids d'une resine au methacrylate de methyle de metal choisie dans un groupe comprenant au moins une resine au methacrylate de methyle de zinc et une resine au methacrylate de dimethyle de zinc; 55 (c) un compose accelerateur de prise de 0,25 partie a 3 parties choisi dans un groupe comprenant (i) le peroxyde de dicumyle, (ii) des derives du peroxyde de dicumyle;

25 EP 0 326 394 B1

(iii) du soufre, et (iv) des produits chimiques donneurs de soufre; C. ledit agent formant charge de remplissage comprend de 15 a 25 parties par poids de matiere de remplissage a fort pouvoir de renforcement, ladite matiere de remplissage pouvant etre choisie dans 5 le groupe comprenant (a) du noir au tunnel moyen traite; et (b) des particules de noir de carbone du type choisi dans un sous -groupe comprenant du N- 1 1 0, du N - 1 21 , du N - 220 et du N - 330, conformement a la norme ASTM D - 1 765.

io 2. Composition selon la revendication 1, caracterisee en ce que ledit agent antidegradant comprend de 0,25 a 2,0 parties par poids d'un antioxydant choisi dans le groupe comprenant au moins les antioxydants des families correspondantes de (a) quinoleines, (b) para-phenylenediamines (PPD) substitutes; is (c) bisphenols encombres.

3. Composition elastomere pouvant etre vulcanisee comprenant une combinaison d'un agent polymere, d'un agent formant charge de remplissage, d'un agent de prise et d'un agent antidegradant corres- pondents, comprenant: 20 A. ledit agent polymere etant choisi dans un groupe comprenant (a) environ 100 parties par poids d'un polymere nitrile fortement sature; (b) un melange de 80 a 90 parties par poids de polymere nitrile fortement sature, et de 10 a 20 parties par poids de nitrile carboxyle; et (c) un melange de 45 a 90 parties de polymere nitrile fortement sature, et de 1 a 5 parties au 25 maximum de polymere nitrile carboxyle, et de 5 a 50 parties de caoutchouc nitrile; B. ledit agent formant charge de remplissage comprenant de 15 a 25 parties par poids d'une matiere de remplissage a fort pouvoir de renforcement. C. ledit agent de prise comprenant (a) de 1,5 a 30 parties par poids d'un oxyde de metal choisi dans un groupe comprenant au 30 moins de I'oxyde de zinc et de I'oxyde de magnesium; (b) de 25 a 50 parties par poids d'une resine au methacrylate de methyle de metal choisie dans un groupe se composant d'au moins une resine au methacrylate de methyle de zinc et une resine au methacrylate de dimethyle de zinc; (c) un compose activateur de prise de 0,25 parties a 3 parties choisi dans le groupe se 35 composant de: (i) peroxyde de dicumyle (ii) derives du peroxyde de dicumyle; (iii) soufre, et (iv) produits chimiques donneurs de soufre; et 40 D. ledit agent antidegradant comprend de 0,25 a 2,0 parties par poids d'un antioxydant choisi dans le groupe se composant d'antioxydants des families correspondantes de (a) quinoleines, (b) para-phenylenediamines (PPD) substitutes (c) bisphenols encombres. 45 4. Composition selon la revendication 1, caracterisee en ce que ledit agent formant charge de remplissage est modifie pour contenir un melange desdites particules de noir de carbone avec de 1 a 15 parties de silice fumee contribuant auxdites 15 a 25 parties par poids de ladite charge de remplissage a fort pouvoir de renforcement. 50 5. Composition selon la revendication 2, caracterisee en ce que ledit agent antidegradant se compose de 0,25 a 2 parties par poids d'un antioxydant dihydro-1,2-trimethyl-2,2,4 -quinoleine (TMQ) polymerise.

55 6. Composition selon la revendication 2, caracterisee en ce que ledit agent antidegradant se compose de 0,25 parties a 2 parties par poids d'une para -phenylenediamine (PPD) substitute.

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7. Composition selon la revendication 2, caracttrist en ce que ledit agent antidegradant comprend une para -phenylenediamine (PPD) substitute qui est la N - isopropyl - phenyl - p - phenylenediamine.

8. Composition selon I'une quelconque des revendications 1, 2 ou 3 caracterisee en ce que ledit 5 polymere nitrile fortement sature mentionnt au paragraphe A presente un degre d'insaturation compris entre 2,5 % et 5%; et en ce que ledit compose activateur de prise se compose d'un disulfure de tetramethyl -thiurame.

9. Composition selon I'une quelconque des revendications 1 , 2 ou 3 caracterisee en ce qu'elle comprend io un caoutchouc nitrile fortement sature, presentant un degre d'insaturation compris entre 1 et 20%, et en ce que ledit compose activateur de prise est le peroxyde de dicumyle.

10. Composition elastomere pouvant etre vulcanisee, selon la revendication 1, caracterisee en ce que ledit agent polymere se compose d'environ 100 parties par poids d'un polymere nitrile fortement sature. 15 11. Proctdt pour la preparation d'une composition elastomere pouvant etre vulcanisee, caracterisee en ce qu'elle comprend un melange de A. environ 100 parties par poids de polymere nitrile fortement sature; B. de 15 a 25 parties par poids d'un agent formant charge de remplissage a fort pouvoir de 20 renforcement, C. un melange activant la prise comprenant (a) de 1,5 a 30 parties par poids d'un oxyde de metal choisi dans le groupe comprenant au moins de I'oxyde de zinc et de I'oxyde de magnesium (b) de 20 a 50 parties par poids d'une resine au methacrylate de methyle de metal choisie dans 25 le groupe comprenant au moins une resine au methacrylate de methyle de zinc et une resine au methacrylate de dimethyle de zinc; (c) un compose activateur de prise de 0,25 parties a 3 parties choisi dans le groupe comprenant (i) du peroxyde de dicumyle, (ii) des derives de peroxyde de dicumyle, 30 (iii) du soufre, et (iv) des produits chimiques donneurs de soufre; et D. Un melange antidegradant contenant de 0,25 a 2 parties par poids d'un antioxydant choisi dans le groupe comprenant au moins les antioxydants des families correspondantes de (a) quinoleines, 35 (b) para-phenylenediamines (PPD) substitutes, et (c) bisphtnols encombrts.

12. Proctdt selon la revendication 11, caracttrist en ce que le mtlange du polymere mentionnt au paragraphe A, comprend, par ailleurs, le mtlange de 80 parties a 90 parties du nitrile fortement saturt, 40 avec de 10 a 20 parties d'un nitrile carboxylt.

13. Proctdt selon la revendication 11, caracttrist en ce que le mtlange du polymere mentionnt au paragraphe A consiste a mtlanger de 45 a 90 parties du nitrile fortement saturt avec de 1 a 5 parties au maximum d'un nitrile carboxylt, et en outre, de 5 a 50 parties d'un caoutchouc nitrile. 45 14. Proctdt selon la revendication 11, caracttrist en ce que le mtlange du mattriau formant charge de remplissage mentionnt au paragraphe B consiste a stlectionner les quantitts prtcistes de mattriau formant charge de remplissage dans un groupe comprenant (a) du noir au tunnel moyen traitt; et 50 (b) des particules de noir de carbone du type stlectionnt dans un sous -groupe comprenant du N- 1 1 0, N - 1 21 , N - 220 et N - 330 conformtment a la norme ASTM D - 1 765.

15. Proctdt selon la revendication 14, caracttrist en ce que le mattriau formant charge de remplissage est modifit ou mtlangt a un autre constituant pour contenir un mtlange de dites particules de noir de 55 carbone avec de 1 a 15 parties de silice fumte contribuant auxdites 15 a 25 parties globales par poids dudit mattriau a fort pouvoir de renforcement.

27 EP 0 326 394 B1

16. Precede selon la revendication 11, caracterise en ce que ledit antioxydant est un antioxydant dihydro- 1,2-trimethyl-2,2,4-quinoleine polymerise (TMQ).

17. Procede selon la revendication 11, caracterise en ce que ledit antioxydant est la para-phenylenedia- 5 mine (PPD).

18. Procede selon la revendication 11, caracterise en ce que ledit antioxydant est connu comme etant la N - isopropyl - phenyl - p - phenylenediamine

io 19. Procede selon la revendication 11, caracterise en ce que le melange avec le polymere mentionne au paragraphe A consiste a utiliser un polymere presentant un degre d'insaturation compris entre 2,5% et 5%; et, en outre, a utiliser, un compose activant la prise qui est le N-cyclo-hexyl-2-benzothiazole sulfanamide donneur de soufre.

is 20. Procede selon la revendication 11, caracterise en ce que le melange avec le polymere mentionne au paragraphe A consiste a utiliser un polymere presentant un degre d'insaturation compris entre 2,5% et 5%; et, en outre, a utiliser, un compose activant la prise qui est le bisulfure de tetramethyle -thiurame.

21. Procede selon I'une quelconque des revendications 11 a 20, caracterise en ce que le polymere 20 mentionne au paragraphe A comprend toutes les qualites de nitrile fortement sature; et en ce que le compose activateur de prise selectionne et mentionne au paragraphe C(c) de la revendication 1 1 est le peroxyde de dicumyle.

22. Procede pour fabriquer un produit formant tuile de chenille moule par compression, lequel produit 25 comprend I'assemblage a des plaques de fixation metalliques combinees au produit vulcanise obtenu a partir de I'une quelconque des compositions definies dans les revendications 1 a 10, caracterise en ce qu'il comprend les etapes consistant a: A. fabriquer un bloc formant ebauche, de taille predetermined, de la composition pouvant etre vulcanisee; 30 B. revetir les plaques de fixation metalliques d'un adhesif approprie active a chaud; C. prechauffer ledit bloc formant ebauche a une temperature d'environ 82 °C; D. prechauffer lesdites plaques de fixation de metal egalement a une temperature de 82 ° C; E. assembler lesdites plaques de fixation et ledit bloc formant ebauche dans un moule qui a ete prechauffe a une temperature d'environ 165°C, qui correspond a une temperature prereglee d'une 35 presse de compression; F. fermer ledit moule et ladite presse de compression, tout en maintenant la temperature de la presse a environ 177°C; G. maintenir simultanement une pression minimale d'environ 13,8 bar a I'interieur dudit moule pendant une periode d'environ 80 minutes; et 40 H. retirer ensuite ledit produit de ladite presse et dudit moule.

23. Produit vulcanise fabrique en chauffant et en moulant par compression les compositions definies dans I'une quelconque des revendications 1 a 10, en utilisant les moules et les pieces d'insertion necessaires auquel le produit vulcanise est lie, caracterise en ce que ledit produit vulcanise presente une taille 45 et une forme predetermines pour constituer un element elastomere particulier appartenant a un groupe d'elements elastomeres, comprenant des tuiles de chenilles, des roues de roulement, et des organes formant douilles pouvant tous etre utilises avec un ensemble formant chenille de tank.

24. Produit pouvant etre vulcanise obtenu par le procede selon I'une quelconque des revendications 1 1 a 50 21, pour lequel ledit produit peut etre un element parmi plusieurs elements de la famille des elements elastomeres de divers groupes selectionnes, constituant (a) des elements formant chenilles de tanks, comprenant au moins des tuiles de chenilles, des roues de roulement et des organes formant douilles pouvant tous etre utilises avec des ensembles formant chenilles de tanks; 55 (b) divers organes de butees et d'arret et de fin de course elastomeres pouvant respectivement se mettre en prise par des mecanismes de deplacement; et (c) divers organes semi -flexibles formant chicanes et jupes pouvant etre utilises avec divers vehicules de type a coussin d'air;

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la formation dudit produit s'effectuant a I'aide de materiel de moulage par compression et selon des procedures de sous -assemblage en association avec des elements metalliques et non metalliques pouvant se combiner, et caracterise en ce que, pour au moins certains elements de la famille, ladite composition elastomere est 5 preformee, de maniere appropriee, par extrusion et formage en blocs, de taille predetermined, qui sont ensuite prechauffes et assembles aux elements pouvant etre combines correspondants, tels que des organes formant plaques de fixation de patins, moyeux de roues et manchons de douilles, dans un moule prechauffe presentant la forme requise, et en ce que le produit final vulcanise est forme selon des procedures de moulage par compression et io chauffage requises.

25. Composition selon la revendication 1, caracterisee en ce que ledit agent polymere est choisi dans le groupe comprenant: (a) environ 100 parties par poids de polymere nitrile fortement sature presentant un degre is d'insaturation compris entre 1% et 5%; (b) un melange d'environ 80 a 90 parties par poids de polymere nitrile fortement sature presentant un degre d'insaturation compris entre 1% et 5%, et de 10 a 20 parties par poids de nitrile carboxyle; et (c) un melange d'environ 45 a 90 parties de polymere nitrile fortement sature presentant un degre 20 d'insaturation compris entre 1% et 5%, et de 1 a 5 parties au maximum de polymere nitrile carboxyle, et de 5 a 50 parties de caoutchouc nitrile.

26. Composition selon la revendication 11, caracterisee en ce en ce que ledit agent polymere est choisi dans le groupe comprenant: 25 (a) environ 100 parties par poids de polymere nitrile fortement sature presentant un degre d'insaturation compris entre 1% et 5%; (b) un melange d'environ 80 a 90 parties par poids de polymere nitrile fortement sature presentant un degre d'insaturation compris entre 1% et 5%, et de 10 a 20 parties par poids de nitrile carboxyle; et 30 (c) un melange d'environ 45 a 90 parties de polymere nitrile fortement sature presentant un degre d'insaturation compris entre 1% et 5%, et de 1 a 5 parties au maximum de polymere nitrile carboxyle, et de 5 a 50 parties de caoutchouc nitrile.

Revendicatlons pour I'Etats contractants sulvants : AT, ES 35 1. Composition elastomere pouvant etre vulcanisee, comprenant une combinaison d'un agent polymere, d'un agent formant charge de remplissage, d'un agent de prise et d'un agent antidegradant, caracteri - see en ce que: (A) ledit agent polymere est choisi dans un groupe comprenant 40 (a) environ 100 parties par poids de polymere nitrile fortement sature; (b) un melange de 80 a 90 parties par poids dudit polymere nitrile fortement sature, et de 10 a 20 parties par poids de nitrile carboxyle; et (c) un melange de 45 a 90 parties dudit polymere nitrile fortement sature, et de 1 a 5 parties au maximum de polymere carboxyle, et de 5 a 50 parties de caoutchouc nitrile; et 45 (B) ledit agent de prise comprend (a) de 1,5 a 30 parties par poids d'un oxyde de metal; choisi dans un groupe comprenant au moins de I'oxyde de zinc et de I'oxyde de magnesium; (b) de 25 a 50 parties par poids d'une resine au methacrylate de methyle de metal choisie dans un groupe comprenant au moins une resine au methacrylate de methyle de zinc et une resine au 50 methacrylate de dimethyle de zinc; (c) un compose activant la prise, a raison de 0,25 partie a 3 parties choisi dans un groupe comprenant (i) le peroxyde de dicumyle, (ii) des derives du peroxyde de dicumyle, 55 (iii) du soufre, et (iv) des produits chimiques donneurs de soufre.

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2. Composition selon la revendication 1, caracterisee en ce que ledit agent formant charge de remplissage comprend de 15 a 25 parties par poids de matiere de remplissage a fort pouvoir de renforcement.

3. Composition selon la revendication 2, caracterise en ce que ledit agent de remplissage peut etre choisi 5 dans un groupe comprenant (a) du noir au tunnel moyen traite; et (b) des particules de noir de carbone du type selectionne a partir d'un sous -groupe comprenant du N - 1 1 0, N - 1 21 , N - 220, et N - 330 conformement a la norme ASTM D - 1 765.

io 4. Composition selon la revendication 1 , caracterisee en ce que I'agent antidegradant comprend de 0,25 a 2,0 parties par poids d'un agent antioxydant choisi dans le groupe comprenant au moins les antioxydants des families correspondantes de (a) quinoleines (b) para-phenylenediamines (PPD) substitutes, et is (c) bisphenols encombres.

5. Composition elastomere pouvant etre vulcanisee, selon la revendication 1 , caracterisee en ce que ledit agent formant charge de remplissage comprend de 15 a 25 parties par poids de matiere de remplissage a fort pouvoir de renforcement; et 20 ledit agent antidegradant comprend de 0,25 a 2,0 parties par poids d'un agent antioxydant choisi dans le groupe comprenant au moins les antioxydants des families correspondantes de (a) quinoleines (b) para-phenylenediamines (PPD) substitutes, et (c) bisphtnols encombrts. 25 6. Composition selon la revendication 3, caracttriste en ce que ledit agent formant charge de remplissage est modifit pour contenir un mtlange desdites particules de noir de carbone et de 1 a 15 parties de silice fumte contribuant auxdites 15 a 25 parties globales par poids dudit mattriau de remplissage a fort pouvoir de renforcement. 30 7. Composition selon la revendication 4, caracttriste en ce que ledit agent antidtgradant se compose de 0,25 a 2 parties par poids d'antioxydant dihydro - 1 ,2 trimtthyl -2,2,4 -quinoltine polymtrist (TMQ).

8. Composition selon la revendication 4, caracttriste en ce que ledit agent antidtgradant se compose de 35 0,25 a 2 parties par poids d'une paraphtnylenediamine (PPD) substitute.

9. Composition selon la revendication 4, caracttriste en ce que ledit agent antidtgradant comprend une paraphtnylenediamine (PPD) substitute qui est la N - Isopropyl - phtnyl - p - phtnylenediamine.

40 10. Composition selon I'une quelconque des revendications 1, 2, 3, 4 et 5 dans lequel ledit polymere nitrile fortement saturt mentionnt dans le paragraphe A prtsente un degrt d'insaturation compris entre 2,5 % et 5%; et caracttrist en ce que ledit compost de prise se compose d'un bisulfure de tttramtthyl- thiurame.

45 11. Composition selon I'une quelconque des revendications 1, 2, 3, 4 et 5 qui contient un caoutchouc nitrile fortement saturt prtsentant un degrt d'insaturation compris entre 1 et 20%, et dans lequel ledit compost activant la prise se compose de ptroxyde de dicumyle.

12. Composition tlastomere pouvant etre vulcaniste, selon la revendication 1, caracttriste en ce que ledit 50 agent polymere se compose d'environ 100 parties par poids de polymere nitrile fortement saturt.

13. Proctdt de preparation d'une composition tlastomere pouvant etre vulcaniste contenant un mtlange de A. environ 100 parties par poids de polymere nitrile fortement saturt; 55 B. de 15 a 25 parties par poids d'un mattriau formant charge de remplissage a fort pouvoir de renforcement, C. un mtlange activant la prise comprenant

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(a) de 1,5 a 30 parties par poids d'un oxyde de metal choisi dans un groupe comprenant au moins de I'oxyde de zinc et de I'oxyde de magnesium (b) de 25 a 50 parties par poids d'une resine au methacrylate de methyle de metal choisie dans un groupe comprenant au moins une resine au methacrylate de methyle de zinc et une resine au 5 methacrylate de dimethyle de zinc; (c) un compose activant la prise de 0,25 parties a 3 parties choisi dans un groupe comprenant (i) le peroxyde de dicumyle, (ii) des derives de peroxyde de dicumyle, (iii) du soufre, et io (iv) des produits chimiques donneurs de soufre; et D. un melange antidegradant contenant de 0,25 a 2 parties par poids d'un antioxydant choisi dans le groupe comprenant au moins les antioxydants des families correspondantes de (a) quinoleines, (b) para-phenylenediamines (PPD) substitutes, et is (c) des bisphenols encombres.

14. Procede selon la revendication 13, caracterise en ce que le melange du polymere mentionne au paragraphe A peut egalement comprendre un melange de 80 a 90 parties du nitrile fortement sature, avec 10 a 20 parties de nitrile carboxyle. 20 15. Procede selon la revendication 13, caracterise en ce que le melange de polymere mentionne au paragraphe A comprend, par ailleurs, le melange de 45 parties a 90 parties du nitrile fortement sature, avec de 1 a 5 parties au maximum de nitrile carboxyle, et en outre, de 5 a 50 parties d'un caoutchouc nitrile. 25 16. Procede selon la revendication 13, caracterise en ce que le melange d'un materiau formant charge de remplissage decrit au paragraphe a consiste a selectionner les quantites precisees de materiau formant charge de remplissage dans un groupe comprenant (a) du noir au tunnel moyen traite; et 30 (b) des particules de noir de carbone du type selectionne dans un sous -groupe comprenant du N - 1 1 0, N - 1 21 , N - 220 et N - 330 conformement a la norme ASTM D - 1 765.

17. Procede selon la revendication 16, caracterise en ce que le materiau formant charge de remplissage est modifie ou melange a un autre constituant pour contenir un melange de dites particules de noir de 35 carbone avec de 1 a 15 parties de silice fumee contribuant auxdites 15-25 parties globales par poids dudit materiau a fort pouvoir de renforcement.

18. Procede selon la revendication 13, caracterise en ce que ledit antioxydant est un antioxydant dihydro- 1,2 trimethyl -2,2,4 quinoline polymerise (TMQ). 40 19. Procede selon la revendication 13, caracterise en ce que ledit antioxydant est la para -phenylenediamine (PPD).

20. Procede selon la revendication 13, caracterise en ce que ledit antioxydant est connu comme etant la 45 N - Isopropyl - phenyl - p - phenylenediamine.

21. Procede selon la revendication 13, caracterise en ce que le melange avec le polymere mentionne au paragraphe A comprend un polymere presentant un degre d'insaturation compris entre 2,5 % et 5%; et en outre, un compose activant la prise qui consiste en un N-cyclo-hexyl-2-benzothiazole donneur 50 de soufre.

22. Procede selon la revendication 13, caracterise en ce que le melange avec le polymere mentionne au paragraphe A consiste a utiliser un polymere presentant un degre d'insaturation compris entre 2,5% et 5%; et en outre, a utiliser, un compose activant la prise qui consiste en du bisulfure de tetramethyl- 55 thiurame.

23. Procede selon I'une quelconque des revendications 13 a 22, caracterise en ce que le materiau polymere mentionne au paragraphe A comprend toutes les qualites de nitrile fortement sature; et en ce

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que le compose activant la prise selectionne mentionne au paragraphe C(c) de la revendication 13 est le peroxyde de dicumyle.

24. Procede pour fabriquer un produit formant tuile de chenille moule par compression, lequel produit 5 comprend I'assemblage a des plaques de fixation metalliques combinees au produit vulcanise obtenu a partir de I'une des compositions definies dans I'une quelconque des revendications 1 a 12, caracterise en ce qu'il comprend les etapes consistant a: A. fabriquer un bloc formant ebauche, de taille predetermined, de la composition pouvant etre vulcanisee; io B. revetir les plaques de Fixation metalliques d'un adhesif approprie active a chaud; C. prechauffer ledit bloc formant ebauche a une temperature d'environ 82 °C; D. prechauffer lesdites plaques de fixation metalliques a une temperature d'environ 82 °C; E. assembler lesdites plaques de fixation et ledit bloc formant ebauche dans un moule qui a ete prechauffe a une temperature d'environ 165°C, qui correspond a une temperature pre-reglee is d'une presse de compression; F. fermer ledit moule et ladite presse de compression, tout en maintenant la temperature de la presse a environ 177°C; G. maintenir simultanement une pression minimale d'environ 13,8 bar a I'interieur dudit moule pendant une periode d'environ 80 minutes; et 20 H. retirer ensuite ledit produit de ladite presse et dudit moule.

25. Produit vulcanise fabrique en chauffant et en moulant par compression les compositions definiees dans I'une quelconque des revendications 1 a 12, en utilisant les moules et les pieces d'insertion de produits necessaires auxquels le produit vulcanise est lie, caracterise en ce que ledit produit vulcanise presente 25 une taille et une forme predeterminees pour constituer un element elastomere particulier appartenant a un groupe d'elements elastomeres, comprenant des tuiles de chenilles, des roues de roulement, et des organes formant douilles pouvant tous etre utilises avec un ensemble formant chenille de tank.

26. Produit pouvant etre vulcanise obtenu par le procede selon I'une quelconque des revendications 13 a 30 23, pour lequel ledit produit peut etre un element parmi plusieurs elements de la famille des elements elastomeres de divers groupes selectionnes, constituant (a) des elements formant chenilles de tanks, comprenant au moins des tuiles de chenilles, des roues de roulement et des organes formant douilles pouvant tous etre utilises avec des ensembles formant chenilles de tanks; 35 (b) divers organes de butees et d'arret et de fin de course elastomeres pouvant respectivement se mettre en prise par des mecanismes de deplacement; et (c) divers organes formant chicanes et jupes pouvant etre utilises avec divers vehicules de type a coussin d'air; la formation dudit produit s'effectuant a I'aide de materiel de moulage par compression et selon des 40 procedures de sous -assemblage en association avec des elements metalliques et non metalliques pouvant se combiner, et caracterise en ce que, pour au moins certains elements de la famille, ladite composition elastomere est preformed, de maniere appropriee, par extrusion et formage en blocs, de taille predetermined, qui sont ensuite prechauffes et assembles aux elements pouvant etre combines correspondants, tels que des 45 organes formant plaques de fixation de patins, moyeux de roues et manchons de douilles, dans un moule prechauffe presentant la forme requise, et en ce que le produit final vulcanise est forme selon des procedures de moulage par compression et chauffage requises.

50 27. Composition selon la revendication 1, caracterise en ce que ledit agent polymere est choisi dans le groupe comprenant: (a) environ 100 parties par poids de polymere nitrile fortement sature presentant un degre d'insaturation compris entre 1% et 5%; (b) un melange d'environ 80 a 90 parties par poids de polymere nitrile fortement sature presentant 55 un degre d'insaturation compris entre 1% et 5%, et de 10 a 20 parties par poids de nitrile carboxyle; et (c) un melange d'environ 45 a 90 parties de polymere nitrile fortement sature presentant un degre d'insaturation compris entre 1% et 5%, et de 1 a 5 parties au maximum de polymere nitrile

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carboxyle, et de 5 a 50 parties de caoutchouc nitrile.

28. Procede selon la revendication 13, caracterise en ce que ledit agent polymere est choisi dans le groupe se composant (a) d'environ 100 parties par poids de polymere nitrile fortement sature presentant un degre d'insaturation compris entre 1% et 5%; (b) un melange d'environ 80 a 90 parties par poids de polymere nitrile fortement sature presentant un degre d'insaturation compris entre 1% et 5%, et de 10 a 20 parties par poids de nitrile carboxyle; et (c) un melange d'environ 45 a 90 parties de polymere nitrile fortement sature presentant un degre d'etat insature compris entre 1% et 5%, de 1 a 5 parties au maximum de polymere nitrile carboxyle, et de 5 a 50 parties de caoutchouc nitrile.

33 EP 0 326 394 B1 EP 0 326 394 B1