Claims
- 1. A process for the production of polyolefin films comprising:
- blending under high shear conditions a polyolefin selected from the group consisting of polypropylene and copolymers of propylene with up to 20 wt. % of ethylene or a C.sub.4 to C.sub.8 mono alpha olefin, and at least one modifier selected from the group consisting of a resin and a resin to form a concentrate mixture comprising 10 to 90 wt. % polyolefin and 10 to 90 wt. % modifier;
- mixing said concentrate with additional polyolefin selected from the group consisting of polypropylene with copolymers of propylene with up to 20 wt. % of ethylene or a C.sub.4 to C.sub.8 mono alpha olefin, to form a blend comprising 70 to 95 wt. % polyolefin and 5 to 30 wt. % modifier; and
- extruding the blend to form a film.
- 2. A process according to claim 1 wherein said concentrate mixture comprises 20 to 60 wt. % of the modifier.
- 3. A process according to claim 1 wherein said polyolefin is polypropylene.
- 4. A process according to claim 1 wherein the polyolefin is isoatactic polypropylene having a density of 0.65 to 0.92 g/cc and a melt flow index of 1 to 15 g/10 min.
- 5. A process according to claim 1 wherein the modifier is hydrogenated.
- 6. A process according to claim 1 wherein the resin has a number average molecular weight below that of the polyolefin.
- 7. A process according to claim 1 wherein the resin has a softening point of 60.degree. to 180.degree. C.
- 8. A process according to claim 1 wherein the polyolefin and modifier are physically blended prior to blending under high shear conditions.
- 9. A process according to claim 1 wherein the polyolefin and modifier are blended in a twin screw extruder.
- 10. A process according to claim 1 where the film contains containing 70 to 90 wt. % polyolefin and 10 to 30 wt. % modifier.
- 11. A process according to claim 1 wherein the film is further uniaxially oriented.
- 12. A process according to claim 1 wherein the film is further biaxially oriented.
- 13. A process according to claim 1 wherein the film is further coated with a layer being a copolymer comprised of 80 to 99 wt. % propylene and 1 to 20 wt. % ethylene.
- 14. A process for the production of polyolefin films comprising:
- blending under high shear conditions a polyolefin selected from the group consisting of polypropylene and copolymers of propylene with up to 20 wt. % of ethylene or a C.sub.4 to C.sub.8 mono alpha olefin, and at least one modifier selected from the group consisting of resin and rosin to form a concentrate mixture comprising 60 to 90 wt % modifier and 10 to 40 wt % polyolefin;
- mixing said concentrate mixture with additional polyolefin selected from the group consisting of polypropylene and copolymers of propylene with up to 20 wt. % of ethylene or a C.sub.4 to C.sub.8 mono alpha olefin, to form a blend comprising 70 to 95 wt % polyolefin and 5 to 30 wt % modifier; and
- extruding the blend to form a film.
Priority Claims (1)
Number |
Date |
Country |
Kind |
87-09446 |
Apr 1988 |
GBX |
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Parent Case Info
This is a continuation of application Ser. No. 07/618,018, filed Nov. 26, 1990, now abandoned, which is a continuation of application Ser. No. 183,820, filed Apr. 20, 1988, now abandoned, which was based upon UK Patent No. 8,709,446 filed Apr. 21, 1987.
US Referenced Citations (3)
Foreign Referenced Citations (6)
Number |
Date |
Country |
82726 |
Jun 1983 |
EPX |
57-57769 |
Apr 1982 |
JPX |
1231861 |
May 1971 |
GBX |
1245250 |
Sep 1971 |
GBX |
1318137 |
May 1973 |
GBX |
1516420 |
Jul 1978 |
GBX |
Continuations (2)
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Number |
Date |
Country |
Parent |
618018 |
Nov 1990 |
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Parent |
183820 |
Apr 1988 |
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