Process for manufacturing a tire safety support and support obtained by this process

A process for manufacturing a cross-linked expanded elastomeric safety support having a cellular structure comprising closed cells, said support being capable of being mounted on a wheel rim within a tire, said process comprising

• kneading by thermomechanical working a rubber composition comprising a diene elastomer having a molar ratio of diene units of less than 15%, water in an amount of from 3 to 6 phr, a reinforcing filler comprising silica in an amount of from 10 to 30 phr and carbon black, a blowing agent that provides for formation of the cellular structure and a vulcanization system, forming the rubber composition after thermomechanical working into a cross-linkable expandable support blank,
• curing the blank in a mold followed by demolding the cured blank, and expanding by decomposing the b owing agent and vulcanizing the cured blank so as to obtain a cross-linked expanded support.

A process for manufacturing a cross-linked expanded elastomeric safety support having a cellular structure comprising closed cells, said support being capable of being mounted on a wheel rim within tire, the process comprising

• kneading by thermomechanical working a rubber composition comprising a copolymer of isobutylene and isoprene, water in an amount of from 3 to 6 phr, a reinforcing filler comprising silica in an amount of from 10 to 30 phr and carbon black in an amount of from 10 to 30 phr, azobisformamide in an amount of from 15 to 30 phr and a vulcanization system, forming the rubber composition after thermomechanical working into a cross-linkable expandable support blank of predetermined section,
• curing the blank in a mold followed by demolding the cured blank, and expanding by decomposing the azobisformamide and vulcanizing the cured blank so as to obtain a cross-linked expanded support.