Rubber composition suitable in vulcanised state as safety support for tyre and such a support

摘要

Rubber composition useful for producing a vulcanized safety support for mounting on the inside of the side wall of a pneumatic tire comprises 100 parts by weight (pbw) diene elastomer, 5-30 pbw of a thermoplastic alpha -olefin polymer with a melting point of at least 150 degrees C and a weight-average particle size of 30-500 mu m, more than 60 pbw reinforcing filler and 3-8 pbw sulfur. Independent claims are also included for the following: (1) a process for producing the rubber composition, comprising mixing the elastomer, filler and powdered polyolefin, admixing a vulcanization system and vulcanizing the composition by heating, each step being performed at a temperature below the melting point of the polyolefin so that the polyolefin remains dispersed in the elastomer in the form of spherical particles; (2) a safety support that is made from the rubber composition and is designed to be mounted on the inside of the side wall of a pneumatic tire so as to support the tire tread in the event of a drop in inflation pressure; (3) a tire including the safety support.