Thermoplastic vulcanizate including rubber block interpolymer

Patent metadata

Field	Value
Publication number	US-10155862-B2
Application number	US-201515539003-A
Country	US
Kind code	B2
Filing date	Dec 11, 2015
Priority date	Dec 23, 2014
Publication date	Dec 18, 2018
Grant date	Dec 18, 2018

Abstract

A thermoplastic vulcanizate composition includes (a) a crystalline thermoplastic polyolefin comprising alpha-olefin monomers having from 2 to 5 carbon atoms, (b) a rubber block interpolymer comprising a first block and a second block having differing chemical or physical properties from the first block, the first block is derived from ethylene, a first alpha-olefin monomer having from 3 to 10 carbon atoms, and a first diene monomer having from 2 to 25 carbon atoms, the second block is derived from ethylene, a second alpha-olefin monomer having from 3 to 10 carbon atoms, and optionally a second diene monomer having from 2 to 25 carbon atoms, and an amount of the block interpolymer in the composition being greater than an amount of the thermoplastic polyolefin in the composition, and (c) a curative system.

First claim

What is claimed is:

1. A thermoplastic vulcanizate composition, comprising:
(a) a crystalline thermoplastic polyolefin comprising alpha-olefin monomers having from 2 to 5 carbon atoms;
(b) a rubber block interpolymer comprising a first block and a second block having differing chemical or physical properties from the first block, the first block being derived from ethylene, a first alpha-olefin monomer having from 3 to 10 carbon atoms, and a first diene monomer having from 2 to 25 carbon atoms, the second block being derived from ethylene, a second alpha-olefin monomer having from 3 to 10 carbon atoms, and optionally a second diene monomer having from 2 to 25 carbon atoms, and an amount of the block interpolymer in the composition being greater than an amount of the thermoplastic polyolefin in the composition; and
(c) a curative system,
wherein the rubber block interpolymer comprises a density from 0.860 to 0.925 g/cm 3 and a DSC melting point temperature of greater than −35° C. and less than 78° C.

2. The thermoplastic vulcanizate composition as claimed in claim 1 , wherein the rubber block interpolymer is an asymmetrical block interpolymer in which the first block is an ethylene/alpha-olefin/diene block and the second block is an ethylene/alpha-olefin block that excludes the diene.

3. The thermoplastic vulcanizate composition as claimed in claim 1 , wherein the rubber block interpolymer in which the first block is an ethylene/alpha-olefin/diene block and the second block is an ethylene/alpha-olefin/diene block.

4. The thermoplastic vulcanizate composition as claimed in claim 1 , wherein an amount of the block interpolymer is greater than 15 wt % and up to 70 wt %, based on the total weight of the thermoplastic vulcanizate composition.

5. The thermoplastic vulcanizate composition as claimed in claim 1 , further comprising an oil.

6. The thermoplastic vulcanizate composition as claimed in claim 5 , wherein an amount of the block interpolymer is from 20 wt % to 70 wt %, an amount of the thermoplastic polyolefin is from 1 wt % to 50 wt %, an amount of the oil is from 1 wt % to 70 wt %, and an amount of the curative system is from 0.1 wt % to 10.0 wt %, based on the total weight of the thermoplastic vulcanizate composition.

7. The thermoplastic vulcanizate composition as claimed in claim 6 , wherein an amount of the block interpolymer is from 25 wt % to 50 wt %, an amount of the thermoplastic polyolefin is from 10 wt % to 30 wt %, an amount of the oil is from 20 wt % to 70 wt %, and an amount of the curative system is from 0.1 wt % to 10.0 wt %, based on the total weight of the thermoplastic vulcanizate composition.

8. The thermoplastic vulcanizate composition as claimed in claim 1 , wherein the first alpha-olefin is the same as the second alpha-olefin and the first diene is the same as the second diene, if included.

9. The thermoplastic vulcanizate composition as claimed in claim 1 , wherein the first block is an ethylene-propylene-diene rubber and the second block is an ethylene-propylene polymer.

10. The thermoplastic vulcanizate composition as claimed in claim 1 , wherein the thermoplastic polyolefin is a polymer having isotactic propylene as a continuous phase with a rubber phase dispersed therein, the rubber phase consisting of the rubber block interpolymer.

Assignees

• Dow Global Technologies Llc

Inventors

• Wu Xiaosong
• Walton Kim L
• Li Pi Shan Colin

Classifications

• C08L23/16

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

• C08F297/08 Primary

  polymerising mono-olefins · CPC title

• C08F297/086

  the block polymer contains at least three blocks · CPC title

• C08L53/00 Primary

  Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers · CPC title

• C08L23/12

  Polypropene · CPC title