Resin composition, transparent film or sheet having elasticity recovering property, and wrap film
AssigneePrime Polymer Co., Ltd.
InventorsMasahiko Endoh, Misao Mukui, Junichi Matsumoto
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Abstract
The present invention provides a propylene-ethylene copolymer which is excellent in a balance between a heat resistance and an elasticity recovering property and has a good transparency and which is improved in peel whitening brought about by mutual adhesion in storing specific to soft materials, a resin composition for a transparent elasticity recovering film or sheet comprising the above copolymer, a transparent elasticity recovering film or sheet and a wrap film.
Claims8
A propylene-ethylene block copolymer having a propylene homopolymer block and a copolymer block, and satisfying the following requisites:
- (1) triad chain ratio fEEE of [EEE]:
- ≦0.1 (mole %),
- (2) product (Re·Rp) of reactivity ratios of ethylene and propylene:
- ≧0.5,
- (3) molecular weight distribution (Mw/Mn):
- ≦3.5,
- (4) enthalpy of melting (ΔH):
- 10 to 60 J/g,
- (5) melting point (Tm):
- ≧105° C. and
- (6) ethylene content:
- ≦10 mole
- wherein the propylene homopolymer block is provided by polymerization of propylene in a first step and the copolymer block is provided by copolymerization of propylene and ethylene in a second step.
A resin composition comprising combination of 60 to 95 mass % of the propylene-ethylene block copolymer as described in claim 1 and 5 to 40 mass % of polyethylene having a density of 0.860 to 0.920 g/cm3.
Dependencies are inferred from the claim text.