GB741646A - Improvements in the production of rubber-resin products - Google Patents

Abstract

Rubber/resin condensation products are produced by acidifying an acid-stabilized conjugated diolefin rubber latex and completely condensing therein the components or partial condensation product of a synthetic resin. The latex may be of natural rubber or of a synthetic rubber such as butadiene polymers and copolymers with styrene or acrylonitrile. The resin components may be aldehydes, such as formaldehyde and furfural, together with primary amines and substituted phenols, such as aniline, p-toluidine, resorcinol, m-amino-phenol and phloroglucinol, or with melamine, urea, thiourea, guanidine or dicyandiamide. Stabilizers specified are oleyl alcohol/ethylene oxide condensation product, cetyl pyridinium bromide and other cationic and non-ionic surface active agents described in U.S.A. Specifications 2,555,068 and 2,661,340. The acids used, e.g. hydrochloric or sulphuric, are preferably added in an amount sufficient to catalyse the reaction, during which bonding between the resin and rubber is said to occur. The resulting mixture is neutralized and the product may be recovered by the usual methods, e.g. coagulation. Ebonite or leather-like or rubbery products may be obtained and those containing up to 70 per cent resin may be plasticized, e.g. with petroleum residues, compounded and vulcanized with the usual ingredients. Fillers such as carbon black, magnesium oxide, zinc oxide, wood flour, chalk, cryptocrystalline clays and calcium silicate may be included and products suitable for shoesoles may be obtained.ALSO:Natural rubber/resin condensation products are produced by acidifying an acid-stabilized latex and condensing therein the components or partial condensation product of a synthetic resin. The resin components may be aldehydes, such as formaldehyde and furfural, together with primary amines and substituted phenols, such as aniline, p-toluidine, resorcinol, m-aminophenol and phloroglucinol, or with melamine, urea, thiourea, guanidine, or dicyandiamide. Stabilizers specified are oleyl alcohol/ethylene oxide condensation product, cetyl pyridinium bromide and other cationic and non-ionic surface active agents as listed in U.S.A. Specifications 2,555,068 and 2,661,340. The acids used, e.g. hydrochloric or sulphuric, are preferably added in an amount sufficient to catalyse the reaction, during which bonding between the resin and rubber is said to occur. The resulting mixture is neutralized and the product may be recovered by the usual methods. Ebonite or leather-like or rubbery products may be obtained and those containing up to 70 per cent resin may be plasticized, compounded and vulcanized with the usual ingredients. Fillers such as carbon black, magnesium and zinc oxides, wood flow, chalk, cryptocrystalline clays and calcium silicate may be included and products suitable for shoe-soles may be obtained.