| abstract |
Polymer melt blends of a homopolymer of propylene or a copolymer of propylene with up to 40 weight percent of another monoolefin, with a homopolymer of one or more of a C10 to C30 alkyl (meth)acrylate or a copolymer containing at least 70 weight percent of the one or more C10 to C30 ester of an alkyl (meth)acrylate with up to 30 weight percent of one or more of a C1 to C9 alkyl (meth)acrylate, the homopolymer or copolymer having a weight-average molecular weight of at least 670,000, exhibit a relative characteristic time, as herein described, at least five (5) times that for the unmodified homo- or copolymer of polypropylene, and a melt strength ratio (as judged by relative sag resistance) at least 5 times that of the unmodified homo- or copolymer of polypropylene. Such blends are useful in thermoforming operations wherein sheet is thermoformed into cartons, containers, appliance housings, and the like. |