Abstract: The invention relates to a crosslinkable rubber composition (I) based on an elastomer and to the process for preparing same. The composition (I) comprises a crosslinking system and a thermoplastic phase which is dispersed into particles, having a melting point MP or softening point SP, a glass transition temperature Tg and optionally a crystallisation temperature Tc, the system comprising sulfur when the elastomer is unsaturated and the phase comprises saturated chains, and a peroxide when the elastomer is saturated, the composition (I) comprising the product of: a) a melt reaction by thermomechanical working of the elastomer and other ingredients except for the system, comprising heating the mixture to a maximum temperature Ta that is greater than MP or SP, then b) mechanical working of the mixture obtained, with addition of the system.

Abstract: The invention relates to a process for preparing a gelled, dried composition forming a monolithic aerogel with a heat conductivity of less than or equal to 40 mW·m?1·K?1 and derived from a resin of polyhydroxybenzene(s) and formaldehyde(s), to this aerogel composition and to the use thereof. This process comprises: a) polymerization in an aqueous solvent of said polyhydroxybenzene(s) and formaldehyde(s) in the presence of an acidic or basic catalyst, to obtain a solution based on the resin, b) gelation of the solution obtained in a) to obtain a gel of the resin, and c) drying of the gel to obtain a dried gel. According to the invention, step a) is performed in the presence of a cationic polyelectrolyte dissolved in this solvent, and the process also comprises a step d) of heat treatment under inert gas of the dried gel obtained in step c) at temperatures of between 150° C. and 500° C.

Abstract: The invention relates to a process for preparing a gelled, dried composition forming a monolithic aerogel with a heat conductivity of less than or equal to 40 mW·m?1·K?1 and derived from a resin of polyhydroxybenzene(s) and formaldehyde(s), to this aerogel composition and to the use thereof. This process comprises: a) polymerization in an aqueous solvent of said polyhydroxybenzene(s) and formaldehyde(s) in the presence of an acidic or basic catalyst, to obtain a solution based on the resin, b) gelation of the solution obtained in a) to obtain a gel of the resin, and c) drying of the gel to obtain a dried gel. According to the invention, step a) is performed in the presence of a cationic polyelectrolyte dissolved in this solvent, and the process also comprises a step d) of heat treatment under inert gas of the dried gel obtained in step c) at temperatures of between 150° C. and 500° C.