Polyolefin thermoplastic silicone elastomers employing radical cure

DETAILED DESCRIPTION OF THE INVENTION Component (A) of the present invention is a thermoplastic resin comprising more than 50% by volume of a polyolefin resin having a softening point of 23.
degree.
C.
to 300.
degree.
C.
As used herein, "softening point" corresponds to the respective melting point of the thermoplastic resin if the resin is at least partially crystalline, or corresponds to the glass transition temperature when the thermoplastic resin is completely amorphous.
Preferably, the softening point is between 50.
degree.
C.
and 300.
degree.
C.
and most preferably between 100.
degree.
C.
and 250.
degree.
C.
The polyolefin resins may be selected from polyethylene, polypropylene, or styrenic block copolymers.
The polyolefin resins may be selected from homopolymers of olefins as well as random graft or block copolymers of one or more olefins with each other and/or up to about 40 mole percent of one or more monomers, which are copolymerizable with the olefins.
Examples of suitable polyolefin resins include homopolymers of ethylene, propylene, butene-1, isobutylene, hexene, 1,4-methylpentene-1, pentene-1, octene-1 , nonene-1 and decene-1, inter alia.
These polyolefins can be prepared using peroxide, Ziegler-Natta or metallocene catalysts, as well known in the art.
Copolymers of two or more of the above mentioned olefins may also be employed as Component (A) and they may also be copolymerized with, e.
g.
, vinyl or diene compounds or other such compounds which can be copolymerized with the olefins.
Specific examples of suitable copolymers are ethylene-based copolymers, such as ethylene-propylene copolymers, ethylene-butene-1 copolymers, ethylene-hexene-1 copolymers, ethylene-octene-1 copolymers, ethylene-butene-1 copolymers and copolymers of ethylene with two or more of the above mentioned olefins.
The polyolefin resin may also be a blend of two or more of the above-mentioned homopolymers or copolymers.
For example, the blend can be a uniform mixture of one of the above systems with one or more of the following: polypropylene, high pressure, low density polyethylene, high density polyethylene, polybutene-1 and polar monomer-containing olefin copolymers such as ethylene/acrylic acid copolymers, ethylene/acrylic acid copolymers, ethylene/methyl acrylate copolymers, ethylene/ethyl acrylate copolymers, ethylene/vinyl acetate copolymers, ethylene/acrylic acid/ethyl acrylate terpolymers and ethylene/acrylic acid/vinyl acetate terpolymers, inter alia