GB593072A - - Google Patents

Abstract

593,072. Plastic compositions. DISTILLERS CO., Ltd., STAUDINGER, J. J. P., and HUTCHINSON, H. M. Sept. 10, 1942, No. 12776. [Class 2 (iii)] [Also in Group V] A plastic composition comprises a synthetic rubber (see Group V) incorporated (either prior to or after copolymerization) in a copolymer of a polymerizable organic compound having an aromatic or heterocyclic ring with a crosslinking agent in an amount such that the copolymer has reduced solubility characteristics, e.g. preferably not exceeding 5 per cent of cross-linking agent. Specified synthetic rubbers are poly - n - butyl acrylate, polyisopropyl acrylate, polyethylene, polyisobutene, polybutadiene, polyisoprene and polychlor-butadiene. Preferably 5-50 per cent of synthetic rubber is incorporated in the composition. Listed polymerizable aromatic or heterocyclic organic ring compounds are styrene, nuclear alkyl-substituted styrenes, indene and N-vinylcarbazole. Cross-linking agents used contain at least two pairs of doubly-linked aliphatic carbon atoms, e.g. p-divinyl benzene, divinyl ether and sulphide, methallyl acrylate, vinyl crotonate, ethylene glycol diacrylate and methacrylic anhydride. The copolymerization may be effected in bulk or in the presence of a diluent or in dispersion. The composition may be compounded with fillers, pigments, dyestuffs or plasticisers. In examples, styrene solutions of (1) polyisobutene and (2) polyisoprene are added to a solution of divinylbenzene in diethyl benzene and copolymerization effected ; crotonyl peroxide may be added in addition to the mixture containing polyisoprene. The products give pliable non-tacky films insoluble in toluene which on weathering show no increase in hardness.