GB379683A - Improvements in and relating to the acceleration of the vulcanisation of natural andartificial varieties of rubber - Google Patents

Abstract

379,683. Vulcanization accelerators. CARPMAEL, A., 24, Southampton Buildings, London.-(1. G. Farbenindustrie Akt.- Ges. ; Frankfort-on-Main, Germany.) April 23, 1931, No. 12083. [Class 70.] The acceleration of the vulcanization of natural and artificial rubber is effected by the application of products obtainable by replacing at least one hydrogen atom attached to nitrogen in aliphatic-, aliphatic-aromaric, hydroaromatic or heterocyclic bases, guanidines or beguanides, by the residue RS- of an aryl compound RSH which does not exert an accelerating action. The accelerators thus produced contain the grouping =N-S-C=, and possess a favourable critical temperature, particularly when used in conjunction with other accelerators. They may be obtained by the action of N-halogen compounds of aliphatic-, aliphatic-aromatic, hydroaromatic- and heterocyclic bases, guanidines or biguanides on aromatic compounds RSH which do not exert an accelerating action ; thus N-chlorpiperidine is reacted with p-thiocresol sodium salt to give p-thiocresol-piperidine. Alternatively a suitable amino base is reacted with an aromatic sulphur halide derived from a compound RSH which does not accelerate.; thus dibutylamine is reacted with p-nitrophenylsulphur chloride in benzene to give p-nitrothiophenol-dibutylamide, and diphenylguanidine is reacted with p-nitrophenyl sulphur chloride in acetic ether to give a thioamide derivative. In examples (1) details are given illustrating the accelerating properties of the reaction products from p-nitrophenyl sulphur chloride and dibutylamine, piperidine, s-diphenylguanidine and o-tolylbiguanide in a rubber mix containing stearic acid, and also of the reaction product of chloropiperidine and p-thiocresol ; (2) details are given showing the accelerating properties of p-nitrothiophenol-dimethylamide, p-nitrothiophenol-ethylcyclohexylamide, p-nitrothiophenol-dibenzylamide, used in conjunction with dibenzthiozyl-2-2<1>-disulphide, p-nitrothiophenol-dicyclohexylamide used in conjunction with dibenzthiozyl-2-2-disulphide, p-nitrothiophenol-pentamethyleneamide used in conjunction with dibenzthiazyl-2-2<1>-disulphide, and also in conjunction with mercaptobenzthiazole. Similar results are obtained by using the reaction products of piperidine and o-nitrophenylsulphur chloride, and of piperidine and phenylsulphur chloride-o-carboxylic acid. Artificial rubber masses derived from butadiene hydrocarbons may similarly be vulcanized.