GB307134A - - Google Patents

Abstract

307,134. White, A. E., (Coodrich Co., B. F.). Dec. 20, 1927. Isomerizing rubber.-Rubber is converted into a heat-plastic material by heating it in the presence of a solvent with a phenol and an acid isomerizing agent such as a strong non-oxidizing mineral acid, or a sulphonic acid or sulphonyl chloride. In an example, to 200 parts of a 5 per cent solution of rubber in benzene, are added 40 parts by weight of phenol and 15 parts of hydrochloric acid. The mixture is heated to 100‹ C. for 40 hours under reflux, the phenol and solvent are removed by distillation in steam, and the residual acid is removed by washing in a hot mill. The resulting product is soluble in the usual rubber solvents to form a base for paints &c., practically insoluble in alcohol, ether, acetone, acetic acid, aniline, water, acids, and alkalies, and may be vulcanized in the usual manner. Balata, guttapercha, synthetic rubbers, and vulcanized or reclaimed rubber containing a low percentage of fillers and pigments, may be converted by the same process. Other solvents such as carbon tetrachloride, gasoline, tetrachlorethane, may be employed, and instead of phenol, cresol, carvacrol, alpha or #, naphthol, catechol, p chlorophenol, may be used. For coating metals &c., the solvent need not be removed, the acid being preferably neutralized, e.g. by ammonia. Specification 249,172 is referred to.