Rubber composition for manufacture of coolant, hot water etc pipes

摘要

A rubber composition for manufacture of a pipe comprises (by wt.) (A) 100 parts brominated copolymer of a 4-7C isoolefin and a p-alkylstyrene (PMS) having a PMS content of 5-25% and a Br2 content of at least 1.5%, the ratio Br2 units to PMS units being 0.15-0.40; together with either (i) (B) 0.1-10 parts Zn white and (C) 1-15 parts brominated alkylphenol resin; (ii) (B), (C) and (D) 25-200 parts inorganic layer compound or 20-200 parts talc; or (iii) (D) only. Independent claims are included for (a) an at least 3-layered pipe in which the inner tube and/or outer layer are of the rubber composition and there is an intermediate reinforcing layer; and (b) production of an at least 2-layered pipe.