Process for the production of an oriented polyolefin film using
multi-component polymer compositions. One polymer component comprises an
isotactic propylene homopolymer produced by the polymerization of
propylene with a Ziegler-Natta catalyst. A secondary component is a
Ziegler-Natta polymerized ethylene-propylene random copolymer or a
metallocene-polymerized ethylene-propylene random copolymer produced by
the polymerization of propylene and ethylene in the presence of a
metallocene polymerization catalyst. The Ziegler-Natta polymerized
copolymer is produced by the polymerization of ethylene and propylene in
the presence of a Ziegler-Natta catalyst and contains no more than 0.5
wt. % ethylene and has a xylene solubles content of at least 2 wt. %. The
primary and secondary polymer components are mixed together to provide a
blend in which, when the secondary component is a Ziegler-Natta
polypropylene, is present in an amount within the range of 5 25 wt. % and
the secondary polymer component is a metallocene-based copolymer present
in an amount of less than 5 wt. %. After mixing the two polymer
components together, the mixture is extruded and the formed into a
biaxially oriented film.