Soft polyolefin compositions and highly filled compounds thereof

Patent metadata

Field	Value
Publication number	US-9290648-B2
Application number	US-201214116183-A
Country	US
Kind code	B2
Filing date	May 9, 2012
Priority date	May 11, 2011
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

Flexible polyolefin compositions with improved balance of properties particularly for applications where softness and ductility at low temperature is requested comprising:
A) from 20 to 40% by weight of a crystalline polymer fraction consisting of a propylene homopolymer, or a copolymer of propylene, or mixtures thereof, said crystalline fraction having a xylene insoluble fraction at 25° C. of at least 90% by weight. B) from 60 to 80% by weight of an elastomeric fraction consisting of a copolymer or blend of copolymers of propylene with one or more alpha-olefins, and optionally with minor quantities of a diene; said copolymer or blend containing ethylene in a quantity lower than 40% by weight.

the fraction soluble in xylene at 25° C. of said polyolefin composition having IVgpc lower than 2.5 dl/g, Mw/Mn (GPC) equal to or higher than 4, Mz/Mw (GPC) equal to or higher than 2.5

Said polyolefin composition optionally further comprising an inorganic filler (II) selected from flame-retardant inorganic fillers and inorganic oxides or salts.

First claim

What is claimed is:

1. An article comprising a polyolefin composition comprising:
a polyolefin composition (I), the polyolefin composition (I) comprises the following fractions:
A) from 20 to 40% by weight of a crystalline polymer fraction selected from the group consisting of a propylene homopolymer, and a copolymer of propylene with one or more comonomers selected from ethylene and a CH 2 ═CHR alpha-olefin, where R is a C 2 -C 8 alkyl radical, or mixtures thereof,
wherein the homopolymer or copolymer contains at least 85% by weight of units derived from propylene,
wherein the crystalline fraction has a fraction insoluble in xylene at 25° C. of at least 90% by weight;

B) from 60 to 80% by weight of an elastomeric fraction comprising a copolymer of ethylene with one or more comonomers selected from propylene and a CH 2 =CHR alpha-olefin, where R is a C 2 -C 8 alkyl radical; said copolymer containing units derived from ethylene in a quantity equal to or less than 40% by weight;
wherein the total weight of A and B fractions is 100%, and
the fraction soluble in xylene at 25° C. of said polyolefin composition has IVgpc lower than 2.5 dl/g,
the ratio Mw/Mn of weight average molecular weight (Mw) to number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is equal to or more than 4,
the ratio Mz/Mw of Z-average molecular weight (Mz) to weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) is equal to or greater than 2.5, and
wherein said polyolefin composition exhibits a flexural modulus of 300 to 600 MPa, and Tg-DSC lower than −40° C., wherein the article is an inner filling, wherein the inner filling is enclosed in an industrial cable or cable sheathing.

2. The article of claim 1 , wherein the polyolefin composition comprises:
20 to 60% by weight of the polyolefin composition (I), and
40 to 80% by weight of an inorganic filler (II) selected from a flame retardant inorganic filler and an inorganic oxide or salt.

3. The article according to claim 1 , wherein the elastomeric fraction comprises a diene at 0.5 to 5% by weight of the fraction (B).

Assignees

• Goberti Paolo
• Pellegatti Giampaolo
• Lunghi Luca
• Basell Poliolefine Srl

Inventors

• Goberti Paolo
• Pellegatti Giampaolo
• Lunghi Luca

Classifications

• C08K3/00

  Use of inorganic substances as compounding ingredients · CPC title

• Y10T428/2933

  Coated or with bond, impregnation or core · CPC title

• C08L23/16

  Ethylene-propylene or ethylene-propylene-diene copolymers · CPC title

• C08L23/10 Primary

  Homopolymers or copolymers of propene · CPC title

• C08L23/14 Primary

  Copolymers of propene (C08L23/16 takes precedence) · CPC title