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UNITED STATES PATENT OFFICE 2,327,772 PASTICZE DAMNOPLAST Gaetano F

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UNITED STATES PATENT OFFICE 2,327,772 PASTICZE DAMNOPLAST Gaetano F Patented Aug. 24, 1943 2,327,772 UNITED STATES PATENT OFFICE 2,327,772 PASTICZE DAMNOPLAST Gaetano F. D'Alelio, Pittsfield, Mass, assignor to General Electric Company, a corporation of New York No Drawing. Application January 16, 1941, Serial No. 374,736 Claims. (C. 260-33) This invention relates to new and useful com it contain at least one N-substituted (partly or positions having properties that render them par completely substituted) or N-unsubstituted sul ticularly useful in the plastics and coating arts. fonamide radical and that, in the other above More particularly the invention is concerned with identified essential radical there be attached to compositions of matter comprising an aminoplast the nitrogen atom identified as N' in the For (more particularly heat-curable and heat-cured naula I at least one hydrogenatom, as a result of aminoplasts) modified, specifically plasticized, Which the compounds are reactable with an alde with a nitrogenous compound selected from the hyde, e. g., formaldehyde, and therefore can in class consisting of (1) aryl compounds having at tercondense under heat with the other compo tached to the aryl nucleus at least one Sulfona 10 nents of the aminoplast (or with the partially mide radical and at least one radical containing formed aminoplast) thereby to become an inte gral part of the resinous mass. the essential unit . As is well known, aminoplasts are synthetic resins derived from amino (including imino) or (HN---- \ . 15 amido (including imido) compounds, a typical more particularly at least one ureidomethylamino example being urea-formaldehyde resin (refer radical, and (2) aldehyde reaction products of ence: Modern Plastics, vol. 17, No. 2, October, the aryl compounds of (1), which aryl compounds 1939, page 433; U. S. Patent 2,214,851, D'Alelio). Other examples of aminoplasts are aminotriazine may be represented graphically by the formula aldehyde resins (e. g. melamine-formaldehyde 20 resins), urea - aminotriazine - aldehyde resins, (I) HN-----aryl-so aminodiazine-aldehyde resins, protein-aldehyde The Sum of the radicals of Formula I that are resins, (e. g., casein-formaldehyde resins), ani introduced into the aryl nucleus may vary from line-aldehyde condensation products, benzene di two up to the combining power of the particular 25 sulfonamide-aldehyde resins, sulfanilamide-alde hyde resins, resinous condensation products of aryl nucleus. For example, taking a benzene nu aldehydes such as formaldehyde with polyamides cleus as illustrative of the aryl radical, there may as, for instance, malonic diamide, maleic diamide, be attached thereto one, two or three fumaric diamide, itaconic diamide, etc. --SO N In the commercial utilization of aminoplasts in 30 the plastics and coating arts, it is frequently nec radicals and one, two or three essary to modify the potentially heat-curable aminoplast by incorporating therein a plasticizer in Order that the aminoplast will flow properly -----NH in the particular coating composition or, in the radicals, or one 35 case of thermosetting aminoplast molding com positions, will show good flow characteristics dur ing molding. If improper or insufficient plastic radical and one to five flow occurs during the molding operation, the 40 molded articles may show streaked or wavy sur faces. Furthermore, if the plasticity of the nold ing composition is not sufficient, lack of physical radicals, or one homogeneity as the result of incompletely knitted : -N-(-N-(-NH granules often characterizes massive moldings. From the foregoing it will be seen that par ticularly in the molding of heat-curable, plasti radical and one to five cized aminoplasts it is important that the plasti -SON cizer have certain physical characteristics. It should improve the flow of the molding compound radicals. The unsatisfied single valencies in the 50 during molding without retarding the curing of described radicals may be satisfied by hydrogen the resin at molding temperatures. It should be or any monovalent organic substituent, more par compatible with the aminoplast both at normal ticularly substituted or unsubstituted hydrocar and at elevated temperatures and should not bon radicals. The unsatisfied double valency in "bleed' from the aminoplast during or after the radical molding. It should not discolor, or impart an odor to, or lessen the water resistance, electrical properties, mechanical strength and other use may be satisfied by a divalent atom or radical, ful properties of the cured aminoplast. The sub e.g., oxygen, sulfur, selenium, =NH, etc. The stances that are able to meet these requisites are only requirement of the aryl compound is that 60 extremely rare. Urea and various substituted 2 2,327,772 ureas, phenols, aniline, toluene sulfonamides and effectively to plasticize the heat-curable amino acid bodies heretofore have been used or Sug plast but would do this without retarding its gested as plasticizers for aminoplasts, but none curing rate and without sacrifice of the useful has been entirely satisfactory. In most cases the properties of the cured aminoplast. improvement in plasticity was attained at the 5 The Organic compounds with which amino sacrifice of some other useful property. For ex plasts are plasticized in accordance with the ample, the addition of urea decreases the Water teachings of the present invention may be de resistance of the molded article. Phenols impart scribed more particularly as compounds having color and odor, while aniline not only imparts the graphic formula, e color and odor but also retards the cure of the resin during molding. O I have discovered that mono and poly aryl . .\?. (..." compounds having attached to the aryl nucleus (II) HN------- ---son/ at least one Sulfonamide radical and at least One l, J.MVTY) radical containing the essential unit Where . .Y ( EN-C-N-C-N--/ more particularly at least one ureidomethylamino radical, and aldehyde reaction products of such 20 aryl compounds constitute a class of materials represents a mono or poly aromatic nucleus, e.g., that meet the above-mentioned requirements for benzene, halogeno aromatic (e. g., halogeno ben a plasticizer for aminoplasts. These organic Zene), alkylated aromatic (e. g., alkylated ben compounds not only effectively plasticize the Zene), hydroxylated aromatic (e.g., hydroxyben heat-convertible aminoplasts So that the amino Zene), alkoxy aromatic (e. g., alkoxy benzene), plast has good flow characteristics during mold 2 5 aryloxy aromatic (e. g., phenoxy benzene), ing, but they accomplish this result without re acetoxy aromatic (e. g., acetoxy benzene), car tarding the curing of the aminoplast during boalkoxy aromatic (e. g., carboalkoxy benzene), molding. Furthermore, the aminoplast is in arylated benzene (e. g., phenyl benzene), naph ternally plasticized without any noticeable de thalene, etc., nuclei. R may be either hydrogen crease in the other valuable properties of the 30 or a monovalent organic radical, more particu heat-hardened aminoplast, such as heat- and larly a substituted or unsubstituted hydrocarbon water-resistance, dielectric strength, mechani radical, e. g., aryl (including naphthyl), aralkyl, cal strength, surface appearance, Color, odor, etc. alkyl, alkaryl, acyl, hydrocyclic, heterocyclic, etc., Another advantage accruing from the use of radicals, or nitro, halogeno, carboalkoxy, acet these organic compounds is that they are able Oxy, amido, imido, amino, nitrilo, etc., derivatives to intercondense with the potentially reactive of such radicals. I prefer to use compounds aminoplast and, therefore, cannot "bleed' from Wherein R represents hydrogen. Y may be a the molding composition or molded article since divalent atom or radical, examples of which have they become an integral part of the resin mole 40 been given heretofore with reference to the un cule. Also, larger amounts of plasticizer can be satisfied double valency of the carbon atom to tolerated in the compositions than usually has which Y is attached, but preferably is either oxy been possible with otherwise plasticized amino gen or Sulfur. In Formula II m and n' are in plasts, and yet not impair the water resistance tegers and each is at least 1, the sum of n and n' of the molded article. These results were quite varying from 2 up to the combining power of the surprising and unexpected, since in no way could particular nucleus. it have been predicted from the known proper More specific examples of compounds compris ties of these Organic compounds or of amino ing the plasticizers used in carrying the present plasts that such compounds not orily would serve invention into effect are listed below: NECONE-CBNH-CH-SO2NH NECON-CENE-CH-SONH NECONH-CHNI-CI-SONIC . NHCONH-CHNI-CH-SO2NHCH NH2CONH-CHNH-CH-SON (CH) NH,CONH-CHNH-CH-SO2N(CHCH);o NHCONH-CHNH-CH-SO2N(CH2CHOH) NECON-CHNI-CI-SONICICIO COC *NHCONH-CHNB-CH-SONHCH2CHC NICON-CENI-CI-SO2NCHCH NH, CoNEI-CHNH-CH-SONHCH, CH,NHC ONH NH2CONE-CHNH-CH-SO2NHCH-CH-O C.I. *NICONH-CH-NH-CH-S ONBCHCHNHOS-CH-NHCONEINo H3CNEICON-CN-C-SON-CE-SONE *NHCONH-CHNH-CH-SONHCHCHNHOCCHC CHNHCONH-CHNH-CH-SO2NH &HNHC ONE-CHNI-CI-SO2Na 2,327,772 3 compound showed practically no plastic flow and did not knit or fuse together very well during NHHC) molding. The plasticized compound, on the *NEIACONH-CH2NH-CH-SONHC-NH other hand, showed excellent plastic flow dur HNO2S-CH-NHCHNHCONHCHNH-CH-SONE ing molding and yielded molded articles that 5 were well knitted or fused together into a strong NEC oNH-CHNH-O-sonich.Nho ONH molded piece of excellent surface characteristics.
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