A HEAT-EXPANDABLE RUBBER COMPOSITION

摘要

A rubber composition usable that is heat-expandable in the unvulcanized state and expanded in the vulcanized state; in the unvulcanized state, said composition comprises a diene elastomer such as natural rubber and/or a polybutadiene, more than 50 phr of a reinforcing filler such as silica and/or carbon black, between 3 and 30 phr of a carbonate and/or a hydrogen carbonate, wherein the carbonate or the hydrogen carbonate comprises sodium or potassium, and between 3 and 60 phr of a hetero-cycloaliphatic acid ammonium salt, wherein a total content of the carbonate or the hydrogen carbonate and the hetero-cycloaliphatic acid salt is greater than 10 phr. The combined use of the carbonate and/or the hydrogen carbonate and the hetero-cycloaliphatic acid ammonium salt makes it possible to greatly shorten curing time of the rubber composition.