Patent ID: 7763703

Claim:
A process for preparation of a synthetic rubber (B), comprising exposing a synthetic rubber (A) to the effect of ultrasound via immersion of a sonotrode into a solution, in a solvent, of the synthetic rubber (A), wherein the resultant synthetic rubber (B) has a lower weight-average molecular weight (M w ) than the synthetic rubber (A), and the polydispersity of the synthetic rubber (B) is less than or equal to 2, wherein synthetic rubber (B) is selected from the group consisting of nitrite rubbers (NBR), hydrogenated nitrite rubbers (HNBR), ethylene-vinyl acetate copolymers EVM, EPDM rubbers, emulsion styrene-butadiene rubber (ESBR), chlorine rubbers (CR), polybutadiene rubbers (BR), acrylate rubbers (ACM), fluororubbers (FKM), IIR and halo IIR; and synthetic rubber (A) is selected from the group consisting of nitrile rubbers (NBR), hydrogenated nitrite rubbers (HNBR), ethylene-vinyl acetate copolymers EVM, EPDM rubbers, emulsion styrene-butadiene rubber (ESBR), chlorine rubbers (CR), polybutadiene rubbers (BR), acrylate rubbers (ACM), fluororubbers (FKM), IIR and halo IIR.