GB955078A - Improvements relating to synthetic rubber - Google Patents

Abstract

A process for stabilizing a synthetic elastomer made by means of a catalyst comprising an iodide of a metal of Group IV to VIII of the Periodic Table of Mendel<\>aeef comprises incorporating in the elastomer as stabiliser one or more of the following compounds p-substituted phenylamines in which the substituent is o-p-directing, p-alkylaminophenols, p,p1-dibutoxydiphenylamine, N,N1 - dialkyl - p - phenylenediamines, N - phenyl - N1-alkyl - p - phenylene - diamines, p-alkylmercaptophenols, alkyl thioureas, dithiocarbamate esters, mercaptobenzthiazole, thioamides, and triaryl phosphites in association with antioxidants. The elastomer may be a cis-polybutadiene prepared with a titanium tetraiodide-aluminium alkyl catalyst. Convetional additives, e.g. carbon black and curatives may be added with the stabilizers. Specified stabilizers are p-octylaminophenol, diphenyl-p-phenylene diamine, p,p1-di-n-butoxy diphenylamine, N-phenyl-N1-propyl and N-phenyl-N1-isopropyl-p-phenylenediamine, p-octylmercaptophenol, dibutyl thiourea, tributyl thiourea, N-N1-dioctyl-p-phenylenediamine, ethylene bis (N,N-dibutyl dithiocarbamate), mercapto benzthiazole and tris-(nonylphenyl) phosphite in association with an equal weight of phenyl-b -naphthylamine or hydroquinone.