Patent ID: 8093336

Claim:
A process for producing a heterogeneous polymer blend comprising: (a) less than 20% by weight (based on the total heterogeneous polymer blend) of a dispersed phase comprising a thermoplastic first polymer having a crystallinity of at least 30%; and (b) a continuous phase having a crystallinity of less than 20% and comprising an elastomeric second polymer different from said thermoplastic first polymer and a hybrid species, said hybrid species comprising a branch-block copolymer having an amorphous backbone and crystalline side chains originating from said thermoplastic first polymer, wherein at least 20% by weight of said continuous phase is insoluble in xylene and substantially free of curatives added to effect post-polymerization cross-linking, the process comprising: (i) polymerizing at least one first monomer comprising a C 2 to C 20 olefin to produce the thermoplastic first polymer; (ii) contacting at least part of said thermoplastic first polymer with a plurality of comonomers comprising at least one C 3 to C 20 olefin and at least one polyene under conditions sufficient to polymerize said comonomers to produce, and simultaneously cross-link, said elastomeric second polymer as finely divided particles.