Compositions for improved orientation processing

In a process for producing a polyolefin film, the steps comprising:

• a. providing a polymer mixture comprising an isotactic propylene-ethylene co-polymer containing no more than 1.0 weight percent ethylene, and having incorporated therein:
• a processing modifier selected from the group consisting of a resin and a rosin, in an amount within the range of 1 to 30 weight percent of said mixture, said resin selected from the group consisting of polyterpene resins, petroleum resins, polyindene resins, coumaroneindene resins, and styrene resins, said rosin being selected from the group consisting of wood rosin, gum rosin, toll oil rosin including hydrogenated, partially hydrogenated, dehydrogenated, and disproportionated polymerization products thereof;
• and
• a syndiotactic polypropylene in an amount within the range of 2 to 10 weight percent of said mixture;
• and
• b. forming a biaxially oriented film layer of said polymer mixture having an exposed surface by stretching said polymer mixture in longitudinal and transverse directions.

In a process for producing a polyolefin film, the steps comprising:

• a. providing a propylene polymer composition of isotactic polypropylene and syndiotactic polypropylene produced by the method of polymerizing propylene in the presence of an isospecific catalyst and a syndiospecific catalyst, said catalysts being present in relative amounts sufficient for said propylene polymer to contain syndiotactic polypropylene in an amount within the range of 2 to 10 weight percent;
• b. providing a processing mixture of said propylene polymer and a modifier selected from the group consisting of a resin and a rosin, in an amount within the range of 1 to 30 weight percent of said mixture, said resin selected from the group consisting of polyterpene resins, petroleum resins, polyindene resins, coumaroneindene resins, and styrene resins, said rosin being selected from the group of wood rosin, gum rosin, toll oil rosin including hydrogenated, partially hydrogenated, dehydrogenated, and disproportionated polymerization products thereof;
• and
• c. forming said mixture into a film layer having an exposed surface.

In a polyolefin film, the composition comprising:

• a. a film layer having an exposed surface formed of a mixture of:
• a propylene polymer selected from the group consisting of isotactic propylene homopolymer and an isotactic propylene-ethylene co-polymer containing no more than 1.0 wt. % ethylene,
• a syndiotactic propylene, and
• a processing modifier selected from the group consisting of a resin and a rosin, said resin selected from the group consisting of polyterpene resins, petroleum resins, polyindene resins, coumaroneindene resins, and styrene resins, said rosin being selected from the group consisting of wood rosin, gum rosin, toll oil rosin including hydrogenated, partially hydrogenated, dehydrogenated, and disproportionated polymerization products thereof;
• and
• b. said syndiotactic propylene and said modifier present in said mixture in relative amounts effective to produce a biaxially-oriented polyolefin film capable of being stretched up to 9 times its original length in the machine direction and stretched in the transverse direction at a temperature equal to or less than 166° C.