Heterogeneous in-situ polymer blend

Patent metadata

Field	Value
Publication number	US-9644092-B2
Application number	US-201414315451-A
Country	US
Kind code	B2
Filing date	Jun 26, 2014
Priority date	Jun 22, 2005
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

A heterogeneous in-situ polymer blend comprising a continuous phase comprising a polypropylene having a crystallinity of at least 30% and a melting point temperature T m greater than 130° C., and a heat of fusion ΔH f greater than 65 J/g; and a dispersed phase comprising particles of an elastomeric copolymer dispersed in the continuous phase and having an average particle size of less than 5 micron, the elastomeric copolymer comprising ethylene units and 0.001 to 5 wt % diene by weight of the copolymer, and having a crystallinity of less than 20% and being at least partially cross-linked such that the degree of cross-link is at least 20%.

First claim

The invention claimed is:

1. A heterogeneous in-situ cross-linked polymer blend comprising:
(a) a continuous phase comprising a polypropylene having a crystallinity of at least 30% and a melting point temperature T m greater than 140 ° C., and a heat of fusion ΔHf greater than 65 J/g, and comprising vinyl terminal groups within a range from 0.4 to 1.0 vinyl/chain; and
(b) 50 wt % or more by weight of the blend of a dispersed phase comprising particles of an elastomeric copolymer dispersed in the continuous phase and having an average particle size of less than 5 micron, the elastomeric copolymer comprising from 20 to 60 wt % of C3 to C20 α-olefin units by weight of the copolymer, 0.001 to 5 wt % of diene units by weight of the copolymer, and the remainder of the elastomeric copolymer being ethylene-derived units, and having a crystallinity of less than 20% and being at least partially cross-linked such that the degree of cross-link is at least 20%, wherein the diene is selected from the group consisting of 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene, 1,10-undecadiene, 1,11-dodecadiene, 1,12-tridecadiene, and 1,13-tetradecadiene;
(c) the blend having a Tensile Strength at break of 0.5 MPa or more, a Tension set of 80% or less, and a melting point temperature T m within a range from 145° C. to 170° C. with no post-polymerization vulcanization; and
(d) wherein no cross-linking agent is present, and the discrete particles of the elastomeric copolymer are produced by an in-situ cross-linking taking place concurrently with the synthesis of the elastomeric copolymer.

2. The in-situ cross-linked polymer blend of claim 1 wherein no more than about 50 wt % of the elastomeric copolymer is extractable in cyclohexane at 23° C.

3. The in-situ cross-linked polymer blend of claim 1 , wherein the degree of cross-link is at least 30%.

4. The in-situ cross-linked polymer blend of claim 1 , wherein the polypropylene is a homopolymer.

5. The in-situ cross-linked polymer blend of claim 1 , wherein the polypropylene is a copolymer comprising up to 9 wt % of alpha-olefins having 2 or from 4 to 12 carbon atoms.

6. The in-situ cross-linked polymer blend of claim 1 , wherein the blend has a ΔHf within the range from 18 J/g to 75 J/g.

7. The in-situ cross-linked polymer blend of claim 1 , wherein the average particle size of the particles of the elastomeric copolymer is between about 50 nanometers and less than 5 microns.

8. The in-situ cross-linked polymer blend of claim 1 , wherein the average particle size of the particles of the elastomeric copolymer is between about 100 nanometers and about 1 micron.

9. The in-situ cross-linked polymer blend of claim 1 , and further including one or more additives selected from fillers, extenders, plasticizers, antioxidants, stabilizers, oils, lubricants, and additional polymers.

10. The in-situ cross-linked polymer blend of claim 1 , the polypropylene having a T m within the range from 145 to 170° C.

11. The in-situ cross-linked polymer blend of claim 1 , the elastomeric copolymer comprising within the range from 1.0 wt % to 5 wt % diene units.

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Jiang Peijun
• Dekmezian Armenag
• Mehta Aspy K
• Jacob Sunny
• Narvaez Jr Andrew G
• Shirodkar Pradeep P
• Weng Weiqing

Classifications

• C08L23/04

  Homopolymers or copolymers of ethene · CPC title

• C08L2205/22

  Mixtures comprising a continuous polymer matrix in which are dispersed crosslinked particles of another polymer · CPC title

• C08L91/00

  Compositions of oils, fats or waxes; Compositions of derivatives thereof · CPC title

• C08L2207/02

  Heterophasic composition · CPC title

• C08L2312/00

  Crosslinking · CPC title