Ethylene polymer blends and oriented articles with improved shrink resistance

Patent metadata

Field	Value
Publication number	US-9890273-B2
Application number	US-201113807088-A
Country	US
Kind code	B2
Filing date	Jun 24, 2011
Priority date	Jul 6, 2010
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

The invention provides an oriented article, for example, a yarn, tape or filaments made from a three component polymer blend.

First claim

We claim:

1. An oriented monofilament that is fabricated from a polymeric blend comprising, based on 100 parts of total polymer:
(a) 20 to 50 parts of a first component (A) comprising a homogeneous ethylene polymer having a density between 0.85 and 0.90 gm/cm 3 , and a Mw/Mn less than 3, and a melt index (I 2 ) between 0.5 and 5 gm/10 minutes; and
(b) 30 to 80 parts of a second component (B) comprising a heterogeneous branched ethylene polymer having a density between 0.91 and 0.945 gm/cm 3 , and a Mw/Mn greater than 3.5, and a melt index (I 2 ) between 0.5 and 10 gm/10 minutes; and
(c) 2 to 25 parts of a third component (C) comprising an ethylene polymer having a density greater than 0.945 gm/cm 3 , and a melt index (I 2 ) between 0.01 and 10 gm/10 minutes.

2. The article of claim 1 wherein the polymeric blend has a relationship between stiffness, in cN/tex/mm, and density, in g/cm 3 , such that stiffness ≦4.8364(density)−4.3324.

3. The article of claim 1 , wherein the monofilament is used in artificial turf.

4. The article of claim 1 in which the homogeneous ethylene polymer of the first component is a substantially linear ethylene copolymer.

5. The article of claim 1 in which the homogeneous ethylene polymer of the first component is a linear ethylene copolymer.

6. A process for forming the oriented article of claim 1 in which:
(a) the first and second components are blended in situ during the formation of such components in one or more polymerization reactors, to thereby form a blend component (AB), and
(b) the third component (C) is formed in separate polymerization reactor(s), and
(c) the third component is blended ex situ with the partial blend (AB) to form the polymeric blend of claim 1 , and
(d) the polymeric blend is then processed to form the oriented article.

7. A process for forming the oriented article of claim 1 in which:
(a) the first and third components are blended in situ during the formation of such components in one or more polymerization reactors, to thereby form a blend component (AC), and
(b) the second component (B) is formed in separate polymerization reactor(s), and
(c) the second component (B) is blended ex situ with the partial blend (AC) to form the polymeric blend of claim 1 , and
(d) the polymeric blend is then processed to form the oriented article.

8. A process for forming the oriented article of claim 1 in which:
(a) the second and third components are blended in situ during the formation of such components in one or more polymerization reactors, to thereby form a blend component (BC), and
(b) the first component (A) is formed in separate polymerization reactor(s), and
(c) the first component (A) is blended ex situ with the partial blend (BC) to form the polymeric blend of claim 1 , and
(d) the polymeric blend is then processed to form the oriented article.

9. The article of claim 1 in which the ethylene polymer of the third component is a homogeneous linear or substantially linear ethylene polymer having an Mw/Mn less than 3.

10. The article of claim 1 in which the ethylene polymer of the third component is a heterogeneous polymer having an Mw/Mn greater than 3.5.

Assignees

• Sandkuehler Peter
• Martin Jill M
• Dow Global Technologies Llc

Inventors

• Sandkuehler Peter
• Martin Jill M

Classifications

• E01C13/08

  Surfaces simulating grass {; Grass-grown sports grounds (grass-like surfaces for skiing E01C13/12)} · CPC title

• C08L2205/025

  containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure · CPC title

• D01F6/46

  of polyolefins · CPC title

• C08L23/08

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

• Y10T442/30

  Woven fabric [i.e., woven strand or strip material] · CPC title