abstract |
An acrylic elastomer composition comprising a carboxyl group-containing acrylic elastomer and a mercaptobenzimidazole gives sealing materials, etc. having improved compression set characteristics, where a vulcanizing agent-vulcanization accelerater combination such as (1) polyfunctional isocyanate compound and at least one of a guanidine, a quaternary onium salt, a tertiary amine and a tertiary phosphine, and (2) a diamine compound and at least one of a guanidine, 1,8-diazabicyclo[5,4,0]-undecene-7, 1,5-diazabicyclo[4,3,0]nonene-5 and their salts is used as a vulcanization system for the composition. |