This invention includes a process for forming a
thermoplastic vulcanizate comprising: (a) admixing a C-H
insertion curing agent with at least one elastomeric phase
polymer to form a first admixture; (b) admixing at least one non-elastomeric
polyolefin with the first admixture to form a second admixture; and (c) heating the second admixture to a temperature at least the
decomposition temperature of the curing agent to crosslink the elastomeric phase while mixing the admixture to an extent sufficient to result in the formation of a
thermoplastic material, hereinafter referred to as a
thermoplastic vulcanizate, and optionally including an additional step (d) of shaping the resulting thermoplastic vulcanizate, especially by heating and foaming or molding the TPV. The C-H
insertion curing agent is preferably selected from
alkyl and
aryl azides (R-N3), acyl azides (R-C(O)N3), azidoformates (R-O-C(O)-N3),
sulfonyl azides (R-SO2-N3), phosphoryl azides ((RO)2-(PO)-N3), phosphinic azides (R2-P(O)-N3) and silyl azides (R3-Si-N3), with poly(
sulfonyl azide) most preferred. Additionally, the invention includes a thermoplastic vulcanizate comprising a blend of: (1) an elastomeric phase crosslinked using a C-H
insertion curing agent dispersed in; (2) at least one non-elastomeric thermoplastic
polyolefin. The invention also includes a foamable composition comprising (1) an elastomeric phase crosslinked using a C-H insertion curing agent dispersed in; (2) at least one non-elastomeric thermoplastic
polyolefin; and (3) from about 0.1 to about 25 percent by weight based on the combined weight of components (1) and (2) of at least one
foaming agent as well as a fabricated part, cable jacket, cable insulation, or foam comprising the thermoplastic vulcanizate or the invention or resulting from the process of the invention.