Patent ID: 7989541

Claim:
A liquid solventless synthetic-rubber-based composition comprising: (a) a low number-average molecular weight non-functional polybutadiene rubber comprising about 75% to about 92% cis-1,4 units; (b) epoxy-terminated low number-average molecular weight rubber comprising butadiene-acrylonitrile copolymer with not less than 3 epoxy terminal groups per molecule, said epoxy-terminated the low number-average molecular weight non-functional polybutadiene rubber being present in the amount of about 2.0 parts to about 4.5 parts by weight for 100 parts by weight of the low number-average molecular weight non-functional polybutadiene rubber; (c) sulfur; (d) a vulcanization accelerator; and (e) an active filler, wherein the sulfur, accelerator, and active filler are each present in the form of powder having a particle size of about 5 μm to about 85 μm.