EP0164493A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Modified polypropylene for film
Assignee: Braskem America Inc
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Filing: 1985-02-15
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Granted: —
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Expires: 2005-02-15
Abstract
Abstract An improved polypropylene blend for biaxial orientation into thin films is made by combining low melt-flow polypropylene, a nucleating agent, and linear low density polyethylene in a pelletizing extruder. Preferably, the low melt-flow polypropylene is formed by cracking a lower melt flow polypropylene with a peroxide agent.
Inventors
- 👤 Victor Martin Dinardo
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 17:51
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/04; C08K5/14; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/08; C08L23/0807; C08L23/0815; C08L2312/00
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
133 words
A polypropylene composition comprising: (a) a propylene polymer having a melt flow of about 2.0 to about 5.0 g/10 min.(L), (b) about 0.10 wt % to about 0.25 wt % dibenzylidene sorbitol nucleating agent and (c) a linear low density ethylene copolymer comprising ethylene copolymerised with olefin monomers having about 4 to about 8 carbon atoms, characterised in that said propylene polymer (a) is a propylene homopolymer; said dibenzylidene sorbitol nucleating agent (b) is a bis (alkylbenzylidene) sorbitol wherein the alkyl groups have about 2 to 18 carbon atoms; and said linear low density ethylene copolymer (c) comprises ethylene copolymerized with about 0.5 to about 7% of said olefin monomers, has a melting point of about 120°C and is present in an amount of about 0.25 wt % to about 2.0 wt %.
Claim 2
Dependent Claim
133 words
A polypropylene composition comprising: (a) a propylene polymer having a melt flow of about 2.0 to about 5.0 g/10 min.(L), (b) about 0.10 wt % to about 0.25 wt % dibenzylidene sorbitol nucleating agent and (c) a linear low density ethylene copolymer comprising ethylene copolymerised with olefin monomers having about 4 to about 8 carbon atoms, characterised in that said propylene polymer (a) is a propylene homopolymer; said dibenzylidene sorbitol nucleating agent (b) is a bis (alkylbenzylidene) sorbitol wherein the alkyl groups have about 2 to 18 carbon atoms; and said linear low density ethylene copolymer (c) comprises ethylene copolymerized with about 0.5 to about 7% of said olefin monomers, has a melting point of about 120°C and is present in an amount of about 0.25 wt % to about 2.0 wt %.
Claim 3
Dependent Claim
40 words
The polypropylene composition of claim 1 wherein the propylene homopolymer is formed by cracking a lower melt flow polypropylene using a peroxide agent selected from the group consisting of dialkyl peroxides in an amount of about 50ppm to about 300ppm.
Claim 4
Dependent Claim
14 words
The polypropylene composition of claim 2 wherein the cracking takes place in an extruder.
Claim 5
Dependent Claim
32 words
The polypropylene composition of any of claims 1 to 3 wherein the propylene homopolymer has a molecular weight distribution of about 2 to about 4 and a crystallisation temperature of about 120°C.
Claim 6
Dependent Claim
15 words
Biaxially oriented sheet made from the polypropylene composition of any of claims 1 to 4.
Claim 7
Dependent Claim
15 words
Biaxially oriented film made from the polypropylene composition of any of claims 1 to 4.
References Cited (Backward Citations)
No citation records indexed.
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