HIGH SHRINKAGE COPOLYMER FILM.

摘要

A biaxially oriented polymer shrink film having a machine direction (MD) shrinkage of greater than a transverse direction (TD) shrinkage such that TD is less than or equal to MD/2 in the range of 100 degree C to 140 degree C. The film comprises at least one of the following: (a) a polyolefin copolymer; (b) a polyolefin terpolymer; (c) blends of polyolefin copolymers and homopolymers; (d) blends of polyelefin copolymers and terpolymers; (e) blends of polyolefin terpolymers and homopolymers; and (f) blends of polyolefin copolymers, homopolymers and terpolymers; wherein the copolymer comprises a first and second monomer. The first monomer is selected from the group consisting of ethylene, propylene, butylene and mixtures thereof; and the second monomer is selected from the group consisting of alpha olefin monomers having two to ten carbon atoms and mixtures thereof. The first monomer is present in the range of 99.5 percent to 75 percent by weight and the second monomer is present in the range of 0.5 percent to 25 percent by weight. The terpolymer comprises: (i) a primary monomer of ethylene, propylene, butylene and mixtures thereof; (ii) a secondary monomer of alpha olefin monomers having two to ten carbon atoms and mixtures thereof; and (iii) a tertiary monomer of alpha olefin monomers having two to ten carbon atoms and mixtures thereof, wherein the primary monomer is present in the range of 50 percent to 99 percent by weight and the secondary and tertiary monomers are present in the range of 0.5 percent to 49.5 percent by weight. The homopolymer is polyethylene, polypropylene and polybutylene.