GB809316A - Chloroprene polymers containing tri-substituted thiourea accelerators - Google Patents

Abstract

A vulcanizable composition comprises an unvulcanized chloroprene polymer and from 0.05 to 5.0 per cent by weight of the polymer of a thiourea accelerator having the general formula <FORM:0809316/IV (a)/1> where each of the radicals R1, R2 and R3 represents an alkyl radical having from 1 to 6 C atoms, an alicyclic radical having from 3 to 6 C atoms, an aryl radical having from 6 to 10 C atoms or an aralkyl radical having from 7 to 10 C atoms. Antioxidants, fillers, colours, metal oxides and softeners may also be added. In examples, Neoprene type W was milled with stearic acid, zinc oxide, magnesia, an antioxidant (octylated diphenylamines), carbon black and, as accelerator, (1) N-phenyl-N1-methyl - N1 - cyclohexyl -, (2) N - phenyl - N1-butyl - N1 - alpha - methylbenzyl -, (3) N - phenyl - N1 - butyl - N1 - benzyl -, (4) N,N1 - diphenyl - N1 - benzyl -, (5) N - phenyl - N,N1-diethyl -, (6) N,N1 - diethyl - N1 - phenyl -, (7) N - ethyl - N1,N1 - dimethyl -, (8) N - isopropyl-N1,N1\h - dimethyl -, (9) N - tertiary - butyl - N1,N1 - dimethyl -, (10) N - butyl - N1,N1 - di-methyl -, (11) N,N1,N1 - tributyl -, (12) N - phenyl - N1,N1 - dimethyl -, (13) N - butyl - N1,N1 - diethyl - or (14) N,N1,N1 - triethyl - thiourea. The chloroprene stocks were then vulcanized by air curing at 307 DEG F. for varying lengths of time.