Epdm foam, producing method thereof, and sealing material

Abstract

An EPDM foam is obtained by foaming a foam composition containing, based on 100 parts by weight of an ethylenepropylenediene rubber, 0.1 to 5 parts by weight of a vulcanizer, 0.1 to 10 parts by weight of a vulcanization accelerator, 1 to 30 parts by weight of a foaming agent, and a foaming auxiliary agent. The vulcanization accelerator contains a thiourea vulcanization accelerator, a thiazole vulcanization accelerator, a dithiocarbamate vulcanization accelerator, and a thiuram vulcanization accelerator such that a thiourea vulcanization accelerator/thiazole vulcanization accelerator/dithiocarbamate vulcanization accelerator/thiuram vulcanization accelerator weight ratio is in a range of 1 to 20/1 to 20/1 to 20/1 to 30.

1 .- 6 . (canceled) 
     
     
         7 . A producing method of an EPDM foam, comprising:
 a preparation step of preparing a foam composition containing, based on 100 parts by weight of an ethylenepropylenediene rubber, 0.1 to 5 parts by weight of a vulcanizer, 0.1 to 10 parts by weight of a vulcanization accelerator containing a thiourea vulcanization accelerator, a thiazole vulcanization accelerator, a dithiocarbamate vulcanization accelerator, and a thiuram vulcanization accelerator such that a thiourea vulcanization accelerator/thiazole vulcanization accelerator/dithiocarbamate vulcanization accelerator/thiuram vulcanization accelerator weight ratio is in a range of 1 to 20/1 to 20/1 to 20/1 to 30, 1 to 30 parts by weight of a foaming agent, and a foaming auxiliary agent; and   a foaming step of heating the foam composition to vulcanize and foam the foam composition.   
     
     
         8 . The producing method of the EPDM foam according to  claim 7 , further comprising:
 a molding step of extruding the foam composition, wherein   the molding step includes vulcanizing and foaming the foam composition extruded by the forming step.