Polyethylene composition for injection molding

Patent metadata

Field	Value
Publication number	US-2016237238-A1
Application number	US-201415029985-A
Country	US
Kind code	A1
Filing date	Sep 24, 2014
Priority date	Oct 15, 2013
Publication date	Aug 18, 2016
Grant date	—

Abstract

A polyethylene composition having density from 0.943 to 1.1 g/cm 3 , comprising:
A) carbon black, or a UV stabilizer, or a mixture of carbon black and a UV stabilizer; B) a polyethylene comprising copolymers of ethylene with 1-alkenes, or mixtures of ethylene homopolymers and said copolymers of ethylene with 1-alkenes, which polyethylene has molar mass distribution width (MWD) M w /M n of from 7 to 15, density of from 0.942 to 0.954 g/cm 3 , a weight average molar mass M w of from 20,000 g/mol to 500,000 g/mol, a MIE of from 1.0 to 3.0 g/10 min, a MIF of from 100 to 200 g/10 min, and a ratio MIF/MIE of from 40 to 50.

First claim

1 . A polyethylene composition having density from 0.943-1.1 g/cm 3 , comprising:
A) carbon black, or a UV stabilizer, or a mixture of carbon black and a UV stabilizer; B) a polyethylene comprising copolymers of ethylene with 1-alkenes, or mixtures of ethylene homopolymers and copolymers of ethylene with 1-alkenes, where the polyethylene has a molar mass distribution width (MWD) M w /M n of from 7-15, a density of from 0.942-0.954 g/cm 3 , determined according to ISO 1183 at 23° C., a weight average molar mass M w of from 20,000 g/mol-500,000 g/mol, a MIE of from 1.0-3.0 g/10 min, a MIF of from 100-200 g/10 min, and a ratio MIF/MIE of from 40-50, where MIE is the melt flow rate at 190° C. with a load of 2.16 kg and MIF is the melt flow rate at 190° C. with a load of 21.6 kg, both determined according to ISO 1133.

2 . The polyethylene composition of claim 1 , comprising 0.25-50% by weight of carbon black and/or 0.01-10% by weight of a UV stabilizer A), all amounts being referred to the total weight of A)+B).

3 . The polyethylene composition of claim 1 , wherein B) contains from 0.7 to 20 CH 3 /1000 carbon atoms as determined by 13 C-NMR.

4 . The polyethylene composition of claim 1 , wherein B) comprises at least one C 3 -C 20 -alpha-olefin monomer species in an amount greater than 3.5% by weight based on the total weight of polyethylene.

5 . The polyethylene composition of claim 1 , wherein B) has a vinyl group content of at least 0.6 vinyl groups/1000 C atoms, and wherein the amount of the polyethylene comprising a molar mass of below 10 6 g/mol, as determined by GPC, is above 95.5% by weight, based on the total weight of the polyethylene.

6 . The polyethylene composition of claim 1 , wherein B) has a η(vis) value of from 0.3-7 dl/g, wherein η(vis) is the intrinsic viscosity as determined according to ISO 1628-1 and ISO 1628-3 in decalin at 135° C.

7 . The polyethylene composition of claim 1 , wherein B) is obtainable in one polymerization step in a single reactor by a mixed catalyst system comprising at least one metallocene.

8 . The polyethylene composition of claim 7 , wherein B) is obtainable by polymerization in the presence of a catalyst composition comprising at least two different single-site polymerization catalysts, comprising at least one hafnocene (a) and at least one iron component (b) having a tridentate ligand bearing at least two aryl radicals, with each aryl radicals bearing a halogen or tertiary alkyl substituent in the ortho-position.

9 . The polyethylene composition of claim 8 , wherein B) is obtainable by copolymerizing ethylene with one or several C 3 -C 20 -alpha-olefin monomer species at a temperature of from 20-200° C. and at a pressure of from 0.05-10 MPa.

10 . The polyethylene composition of claim 1 , further comprising non-polymeric additives such as lubricants and/or stabilizers.

11 . An injection molded article, comprising the polyethylene composition of claim 1 .

12 . The injection molded article of claim 11 , comprising a container of at least 5 L.

13 . The injection molded article of claim 11 , which is an inner part of a tank.

14 . The injection molded article of claim 12 , comprising a container of 5-100 L.

15 . The injection molded article of claim 13 , comprising a slosh baffle.

Assignees

• Basell Polyolefine Gmbh

Inventors

• Hoecker Bernd

Classifications

• C08F10/02 Primary

  Ethene · CPC title

• C08F210/16

  Copolymers of ethene with alpha-alkenes, e.g. EP rubbers · CPC title

• B65D25/02 Primary

  Internal fittings (of containers made by folding or erecting blanks made of paper B65D5/44) · CPC title

• C08L23/06 Primary

  Polyethylene · CPC title

• C08F4/65925

  two cyclopentadienyl rings being mutually non-bridged · CPC title