Film comprising a random copolymer with enhanced ethylene content
A polypropylene resin, useful for the production of biaxially oriented polypropylene (BOPP) film, is provided. The polymer of the present invention is a blend of high crystalline polypropylene homopolymer and a high ethylene ethylene/propylene random copolymer (RCP). The present invention also provides a method of preparing the novel resin as well as a novel BOPP film comprising the resin.
1 . A biaxially oriented polypropylene film comprising a polymer, said polymer comprising:
a. about 70% to about 95% by weight of a polypropylene homopolymer, said polypropylene homopolymer having less than 3% by weight xylene solubles and a crystallinity of at least 55%; and
b. about 5% to about 30% by weight of an ethylene/propylene random copolymer, said ethylene/propylene random copolymer containing greater than about 7.2% to about 15% ethylene by weight.
2 . The biaxially oriented film of claim 1 wherein the ideal processing temperature is about 328° F.
3 . The biaxially oriented film of claim 1 wherein the haze is about 0.57.
4 . The biaxially oriented film of claim 1 wherein the percent transmittance is greater than about 90%.
5 . The biaxially oriented film of claim 1 wherein the clarity is greater than about 95%.
6 . The biaxially oriented film of claim 1 wherein said polymer further comprises at least one additive selected from the group consisting of nucleators, antioxidants, acid neutralizers, slip agents, antiblock agents, antifogging agents, pigments, and combinations thereof.
7 . The biaxially oriented film of claim 1 wherein said film is opaque.
8 . The biaxially oriented film of claim 1 wherein said film is transparent.