GB873123A - N,n-substituted phenylenediamines, and vulcanized rubber containing same - Google Patents

Abstract

A method of inhibiting ozone deterioration of crude rubber products comprises incorporating in an unvulcanized, vulcanizable rubber composition a compound of the formula: <FORM:0873123/IV (a)/1> in which R is an alkyl or cycloalkyl radical, R1 is a hydroxyalkyl radical and R2 is hydrogen or a hydroxyalkyl radical and curing the resultant composition. The anti-ozonant may be used in natural and synthetic rubbers, preferably in an amount of 2%-3%. Compositions are described based on butadiene/styrene copolymer or on smoked sheets and containing various compounds of the above formula as anti-ozonant as well as an anti-oxidant and other conventional rubber additives. The results of dynamic ozone tests and of tensile tests on the rubbers are given.ALSO:The invention comprises compounds of the formula <FORM:0873123/IV (b)/1> where R is an alkyl or cycloalkyl radical, R1 is a hydroxy-alkyl radical and R2 is hydrogen or a hydroxy alkyl radical. The compounds may be used as rubber anti-ozonants and may be prepared by reacting a di-alkyl p-phenylene diamine with an olefin oxide at an elevated temperature. Examples describe the preparation of the N-2-hydroxyethyl derivatives of N,N1-di-isopropyl-, N,N1-di-sec.butyl-, N,N1-di-sec.octyl-, N,N1-di-3-(5-methylheptyl)-and N,N1-di-cyclohexyl-p-phenylene diamine, the N,N1-bis-(2-hydroxyethyl) derivatives of N,N1-di-isopropyl and N,N1-di-cyclohexyl-p-phenylene diamine and of N-2-hydroxypropyl-N,N1-di-isopropyl and N,N1-di-sec.butyl-p-phenylene diamine.