1 3,216,982 United States Patent 0 ice Patented Nov. 9, 1965
1 2 are halides of Groups IVa, Va or VIa metals such as 3,216,982 titanium tetrachloride, zirconium tetrachloride, vanadium CATALYSTS FOR POLYMERIZATIGN tetrachloride and titanium tetraiodide, and oxyhalides Adam Orzechowski, Waltham, and James C. Mac-Kenzie, such as vanadium oxychloride and chromium oxychlo Wellesley Hills, Mass, assignors to Cabot Corporation, ride. Boston, Mass, a corporation of Delaware The conditions under which reaction between the tran No Drawing. Filed Mar. 28, 1963, Ser. No. 268,589 The portion of the term of the patent subsequent to sition metal halide and the ?nely-divided inorganic solid Jan. 18, 1982, has been disclairned can be accomplished are subject to considerable varia 23 Claims. (Cl. 260—88.2) tion as explained in detail in Serial No. 2,861, for ex 10 ample. However, in order to obtain a catalyst com This invention relates to the polymerization and co ponent with exceptionally high activity and reproducible polymerization of mono-ole?ns and/or di-ole?ns such as character it has been found to be all important that the ethylene, propylene, butene-l, styrene, isoprene and buta ?nely-divided inorganic solid be essentially dry and anhy diene and includes within its scope improved catalysts drous (i.e. free of molecular water in any form) at the for the polymerization of the aforementioned classes of time it is brought into contact with the transition metal monomers. halide. In addition, it is recommended that said reaction This case is a continuation in part of copending ap be achieved so as to allow by-products of the reaction plications, Serial No. 2,861, ?led January 18, 1960, and (for example, HCl) to be eliminated from the reaction Serial No. 21,110, ?led April 11, 1960, both by Orze~ zone in order to insure that said reaction goes to com 'chowski and MacKenzie, and both now abandoned. 20 pletion. Generally, said reaction can be carried out by It is a principal object of the present invention to contacting said inorganic solid with said transition metal provide a process for the polymerization of mono-, di-ole halide, preferably in a solution thereof in an inert hydro ?ns and mixtures thereof. carbon medium, and maintaining the two reactants in It is another object of this invention to provide novel intimate contact for a period of time sufficient to effect catalysts for the polymerization of mono-, di-ole?ns and the desired chemical reaction resulting in the chemical mixtures thereof. bonding of the transition metal to the inorganic solid. Other objects of this invention will in part be obvious The length of time required to effect a given amount of and will in part appear hereinafter. such reaction and chemical bonding is largely dependent Said copending applications disclose catalyst com upon the temperature of the reaction mixture. Generally ponents suitable for use in the polymerization and co- ‘ speaking, ‘almost ‘any temperature between about 0° C. polymerization of mono- and di-ole?ns, which com and about 300° C. can 'be used satisfactorily, but room ponents comprise the product of the metathetical reac temperature to about 105° C. is generally de?nitely pre tion carried out under certain conditions between a ferred. Assuming provision is made for intimate con halide-type compound of a Group IVa, Va or VIa metal tact of the dry inorganic solid and the transition metal and hydroxyl groups on the surface of a ?nely-divided 35 halide, the minimum time required to accomplish the particulate inorganic solid. In accordance with the chemical reaction needed will vary from periods of about present invention, it has been discovered that excellent 10 hours at room temperature to periods of about 15 polymerization catalysts are obtained when said catalyst minutes at temperatures of 100° C. or over. Tempera components are combined, under suitable conditions, with tures higher than about 300° C., e.g. 500° C., are com certain organometallic compounds comprising germa 40 pletely needless and therefore of little or no interest. nium, tin or lead. Elimination of by-products of the reaction from the The polymerization and copolymerization of the mono reaction zone, i.e. the reaction medium, can be accom and/or di-ole?ns can be effected at suitable tempera plished in many ways, such as by sweeping the reaction tures within the range of from about -—25° C. to about vessel with an inert gas, by carrying out the reactionat 250° C., and pressures ranging upwardly from about su?iciently elevated temperatures to drive by-products atmospheric pressures to any desired maximum pressure, out of the reaction zone, i.e. usually out of the reaction for example, 30,000 p.s.i.g. or even higher pressures. medium, or by complexing or reacting said by-products Inorganic solids suitable for the purposes of the present with suitable substances such as tertiary arsines, tertiary invention generally include any inorganic compound phosphines, terpenes, terpinenes, tetrasubstituted hydra which is available in ?nely-divided particulate form with 50 zines, carbides such as calcium carbide, and other sub hydroxyl groups on the surface thereof. For example, stances such as sodium hydride which Will react orcom oxides such as alumina, zirconia and silica, silicates such plex with said by-products and thereby eliminate them. as chrysotile, and aluminates such as corundum are all Organometallic compounds suitable for the purposes generally suitable for the purposes of the present inven of the present invention are those compounds conforming tion. For best results, however (as explained in detail 55 to the empirical formula in said copending application Serial No. 2,861), inorganic solids having an average particle diameter of less than about 0.1 microns are de?nitely preferred. Halide-type compounds of Group IVa, Va or VIa 60 (hereinafter generally referred to as transistion metal wherein each R is chosen from the group consisting of halides) suitable for the purposes of the present inven monovalent hydrocarbon radicals, monovalent alkoxy tion, are compounds conforming to the general empirical radicals, monovalent aryloxy radicals, and the halogens; formula p is a number from 0 to 3; each H is a hydride radical; TOaXb 65 t is a number from 1 to 4; M is a quadrivalent metal wherein T is a metal of Groups IVa, Va or VIa (where chosen from the group consisting of germanium, tin the group numbers correspond to the Mendeleev Periodic and lead; and O is oxygen. System); 0 is oxygen; a is number from 0 to 2; each Speci?c examples of R groups for substitution in the X is any halogen; and b is a number from 1 to 6. above formula include methyl, 2-methyl-2-butenyl, n Examples of suitable compounds conforming to said 70 dodecyl, 4~cyclohexylethyl, methylnaphthylethyl, 2,2,1 general formula bicycloheptyl, tolyl, xylyl, xenyl, methoxy, isobutoxy, n T0,,Xb octyloxy, phenoxy and 1,2-naphthoxy. 3,216,982 3 4 Speci?c examples of compounds conforming to the catalyst utilized, the speci?c type of product desired, and formula: the extent of monomer conversion desired in any given run or pass over the catalyst. In general, this variable is readily adjustable to obtain the desired results. There follow a number of illustrative non-limiting ex amples: which are suitable for the purposes of the present inven tion are: trimethylstannane, (CH3)3SnH; triphenylstan Example 1 nane, (C6H5)3SnH; dimethylstannane, (CH3)2SnH2; tri ethylgermane, (CZH5)3GeH; triphenylgermane, To a 2000 milliliter, three neck, glass reaction vessel 10 there is added 20 grams of “Cab-O-Sil,” a pyrogenic (csHsl sGeH silica produced by Cabot Corporation, which has an av tri-a-naphthyl-germane, (a-C1°H7)3G€H; tri-n-hexylger erage particle diameter of 10 millimicrons and a hy mane, (n-CGH1’3)3GeH; di-i-propylgermane, droxyl group content on the surface thereof of about 1.5 15 milliequivalents per gram. To said reaction vessel there is added 1700 milliliters of benzene, and the resulting plumbane, PbH4', germane, Gel-I4; stannane, SnH4; 1,2 slurry is dried by being heated to, and maintained at, dihydrotetramethylstannoxane, (CH3) 2HSnOHSn(CH3) 2; the boiling point of benzene, i.e. about 80° C., for about and the like. 20 hours, while a water/benzene azeotrope is removed The catalysts of the present invention are formed when 20 from. the reaction vessel by periodic distillation until the product of the metathetical reaction (as described about 450 milliliters of distillate has been removed. The above) of hydroxyl groups in the surface of an inorganic vessel is then cooled and charged with 20 millimoles of solid and a transition metal halide is combined in an titanium tetrachloride. The contents of the vessel are inert environment with an organometallic compound at then continuously stirred, and maintained at re?uxing temperatures normally between about 0° C. and about temperature (about 80° C.) for about 6 hours while the 150° C. and at atmospheric pressure, although higher contents of the gas phase are swept by a stream of dry temperatures and pressures can be utilized. Thetem nitrogen. Subsequently, the extent of the reaction be peratures and/ or pressures that are most desirably utilized tween the titanium tetrachloride and the hydroxyl groups with any particular combination of components can be in the surface of the silica is determined by measuring readily determined bearing in mind that temperatures and/ the quantity of HCl that was removed by the dry nitrogen or pressures that cause substantial decomposition of either of the components of the catalyst should be avoided. stream and by testing the liquid contents of the vessel Using the catalysts of this invention, polymerization for the absence therein of titanium tetrachloride, and of mono-ole?n and/ or di~ole?n monomers can be accom said slurry is found to contain 20 milliatoms of titanium plished in the absence of liquids (other than the monomers chemically bound to the surface of said silica. themselves), solvents or diluents, for example, in the gas ' To a 2000 milliliter glass, three neck, reaction ?ask phase, but it is usually more convenient to effect poly equipped with a magnetic stirrer there is introduced merization in the presence of a substantially inert liquid about 100 milliliters of said cocatalyst slurry which con reaction medium. Accordingly, an inert liquid reaction tains about 2 milliatoms of titanium bound to the sur medium is preferably supplied to the reaction zone. face of about 2 grams of silica. Next, in total darkness, Several classes of hydrocarbons or their mixtures which 40 there is added to said vessel a solution comprising about are liquid and substantially inert under the polymeriza 900 milliliters of anhydrous toluene and 8 millimoles of tion conditions of the present process constitute suitable triphenylstannane. The contents of the reaction ?ask liquid reaction media. Thus, various classes of saturated are then continuously agitated in darkness at ambient hydrocarbons such as pure alkanes or cycloalkanes or temperatures for about 24 hours, whereupon it is noted commercially available mixtures, freed of harmful im 45 that the color of the solid phase has changed to a choco purities, are generally suitable for the purposes of the late brown. Said slurry is transferred, in toto, and with present invention. For example, straight run naphthas out exposure to the atmosphere to a 4000 milliliter, stain or kerosenes containing alkanes and cycloalkanes and less steel, stirred autoclave. Next, the autoclave is pres liquid or lique?ed alkanes such as n-hexane, 2,3-dimethyl surized to, and maintained at, about 600 p.s.i.g. with butane, n-dodecane, dimethylcyclopentane, methydecalins, 50 ethylene and is thereafter stirred continuously for about and the like are suitable. Also, members of the aromatic 48 hours at ambient temperature after which the solid hydrocarbon series, such as isop‘ropyl benzene, ethyl reaction products are withdrawn and analyzed. It is toluene, hemimellitene, pseudocumene, isodurene, isoam found that about 142 grams of solid polyethylene have ylbenzene, and particularly the mononuclear aromatic hy been produced. drocarbons such as xylene, mesitylene and xylene-p When under the same conditions either the triphenyl cymene mixtures, and the like are completely suitable. stannane or the silica cocatalyst carrying titanium chem The proportion of surface reacted particulate inorganic ically combined to the surface thereof is utilized alone solid to organometallic compound utilized in preparing as the catalyst, no solid polymer is produced. the catalysts is not usually a critical feature of the process. We have found from experience that a molar ratio of 60 Example 2 from about 0.1 to about 5 millimoles of the organo metallic compound per milliatom of transition metal To a 2000 milliliter stainless steel, stirred autoclave chemically combined with the surface of the ?nely-divided there is introduced 50 milliliters of the cocatalyst slurry solid is to be preferred. produced in Example 1 which contains about 1 milliatom The quantity of catalyst, i.e. comprising both the sur 65 of titanium bound to the surface of about 1 gram of face-reacted ?nely-divided solid and the organo-metallic silica. Next, there is introduced into the autoclave about compound, to be utilized in the polymerization reaction 750 milliliters of anhydrous toluene and 3 millimoles of may vary, but in general, the total quantity of catalyst di-i-propylgermane. The autoclave is heated to, and that need be employed based on the weight of the charg maintained at, about 100° C. with continuous stirring for ing stock is very small particularly when a very ?ne 70 about 6 hours. Said autoclave is then cooled to, and particle size oxide (i.e. having an average particle diam thereafter maintained at about 80° C. and there is in eter of less than about 0.1 micron) is utilized as the in troduced 200 millimoles of 1,3-butadiene and 200 milli organic solid. moles of ethylene. After 24 hours of continuous stirring The contact time or space velocity employed in the the solid product is analyzed and it is found that a buta polymerization process variables such as the particular diene-ethylene copolymer has been produced. 3,216,982 5 . 6 Example 3 wherein T is a metal chosen from the group con sisting of the metals of Groups IVa, Va and VIa; To a 4000 milliliter, three neck, glass reaction vessel O is oxygen; a is a number from 0 to 2; each X there is added 10.6 grams of “Alon,” a pyrogenic alumina is any halogen; b is a number from 1 to 5; and produced by Deutsche Gold- und Silber-Scheideanstalt where said structures are chemically linked directly vormals Roessler which has an average particle diameter from T to at least one oxygen atom in the surface of about 10-40 millimicrons and a hydroxyl group con— of said solid, and tent on the surface thereof of about 0.7 milliequivalent (b) an organometallic compound conforming to the per gram. Next, there is added 2500 milliliters of toluene formula and the resulting slurry is heated to, and maintained at, 10 re?uxing temperature, about llO.6° C., for 14 hours while a toluene/water azeotrope is periodically distilled off until about 500 milliliters of distillate have been re moved. The vessel is cooled and there is then introduced wherein each R is chosen from the group consisting 4 millimoles of vanadium oxychloride. The contents of 15 of monovalent hydrocarbon radicals, monovalent the vessel are thereafter continuously stirred, and main aryloxy radicals, and the halogens; p is a number tained at re?uxing temperature for about 10 hours while from 0 to 3; each H is a hydride radical; t is a num the gas phase is swept by a stream of dry nitrogen. Sub ber from 1 to 4; M is a quadrivalent metal chosen sequently, the extent of the reaction between the vana from the group consisting of germanium, tin and dium oxychlon'de and the alumina is determined by lead; and 0 is oxygen. ' measuring the quantity of HCl removed from the vessel 2. The process of claim 1 wherein in said formula by the nitrogen stream, and by testing the liquid con tents of the vessel for the absence therein of vanadium oxychloride and the said alumina is found to contain T it titanium, each X is chlorine and b is 3. a 4 milliatoms of vanadium bound to the surface of said 3. The proces of claim 1 wherein the substance polym alumina. erized is an a-mono-ole?n. To a 2000 milliliter, stainless steel, stirred autoclave 4. The process of claim 1 wherein the substance polym there is introduced 1000 milliliters of said cocatalyst erized is a di-ole?n having a double bond in the alpha slurry which'contains about 2 milliatoms of vanadium position. chemically bound to the surface of about 5.3 grams of 30 5. The process of claim 1 wherein each X in the for alumina. Next, there is added to said vessel 6 millimoles mula of triethylgermane dissolved in 200 milliliters of anhy TOaXb drous toluene. The resulting mixture is then heated to is chlorine. and maintained at about 110° C. with continuous agita 6. The process of claim 1 wherein in said formula tion for about 4 hours. Said autoclave is then cooled to and thereafter maintained at about 80° C. and there T0,,Xb is then introduced thereinto propylene gas to a total pres T is a metal of Group Na. sure of about 200 p.s.i.g. After 8 hours of continuous 7. The process of claim 1 wherein in said formula agitation the solid product of the reaction is analyzed 40 TOaXb and it is found that polypropylene polymer has been T is titanium. produced. 8. The process of claim 1 wherein in said formula The polymers produced by the process of this inven tion can be subjected to such aftertreatment as may be TOaX‘J desired to ?t them for particular uses or to impart de— T is a metal of Group Va. sired properties. Thus, the polymers can be extruded, 45 9. The process of claim 1 wherein in said formula mechanically milled, ?lmed or cast, or converted to TOaXb sponges or latices. Also, antioxidants, stabilizers, ?llers T is vanadium. such as carbon black or additional silica, extenders, plas ticizers, pigments, insecticides, fungicides, etc., can be 10. The process of claim 1 wherein in said formula incorporated into the polymers. TOaXb Obviously, many changes may be made in the above T is a metal of Group VIa. described examples and procedure without departing 11. The process of claim 1 wherein the substance to be from the scope of the invention. For example, although polymerized is chosen from the group consisting of ethyl only transition metal chlorides are mentioned in the above ene, propylene and butene-l. examples, transition metal bromides, iodides and ?uo 12. The process of claim 1 wherein in said formula rides are also suitable for the purposes of the present invetntion. For example, titanium tetra?uoride is en tirely suitable. Accordingly, it is intended that the above disclosure be M is lead. regarded as illustrative and as in no way limiting the 13. The process of claim 1 wherein in said formula scope of the invention. What we claim is: RpHtMO 4_ (t +1’), 1. A process for polymerizing a substance chosen from 2 the group consisting of mono-ole?ns, mixtures of mono M is tin. ole?ns, di-ole?ns, mixtures of di-ole?ns and mixtures 14. The process of claim 1 wherein in said formula thereof which comprises contacting said substance at temperatures between about —25° C. and 250° C., with R’H‘M°4—c+p) a catalyst comprising the product of the reaction between 2 (a) a ?nely-divided inorganic solid having an aver M is germanium. age particle diameter of less than about 0.1 micron 15. The process of claim 1 wherein in said formula and carrying in chemical combination on the sur R"H‘M°4-