Multiblock copolymer, rubber composition, and tire

Patent metadata

Field	Value
Publication number	US-10125210-B2
Application number	US-201515128449-A
Country	US
Kind code	B2
Filing date	Feb 24, 2015
Priority date	May 2, 2014
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

A multiblock copolymer, obtainable by copolymerization of a conjugated diene compound and a non-conjugated olefin, wherein: a structure of the multiblock copolymer includes A-(B-A)x and/or B-(A-B)x, wherein “A” represents a block portion constituted of monomer units of a non-conjugated olefin, “B” represents a block portion constituted of monomer units of a conjugated diene compound, and “x” represents an integer ≥1; content of the non-conjugated olefin portion is ≤30 mass %; and storage modulus G′ at 130° C., measured by rubber process analysis using a rubber process analyzer, i.e. RPA, according to ASTM D6204, is ≥20 kPa. It is possible to obtain vulcanized rubber and thus a tire having high fracture resistance and high weather resistance from the multiblock copolymer and a rubber composition derived therefrom.

First claim

The invention claimed is:

1. A multiblock copolymer, obtained by copolymerization of a conjugated diene compound and a non-conjugated olefin, wherein:
a structure of the multiblock copolymer includes A-(B-A) x and/or B-(A-B) x , wherein “A” represents a block portion constituted of monomer units of a non-conjugated olefin, “B” represents a block portion constituted of monomer units of a conjugated diene compound, and “x” represents an integer ≥1;
content of the non-conjugated olefin portion is ≤30 mass %;
storage modulus G′ at 130° C., measured by rubber process analysis using a rubber process analyzer, i.e. RPA, according to ASTM D6204, is ≥20 kPa; and
the melting point of the multiblock copolymer determined by differential scanning calorimetry measurement according to JIS K7121: 1987 is equal to or lower than 120° C.

2. The multiblock copolymer of claim 1 , wherein, provided that difference between storage modulus G′ at 130° C. and storage modulus G′ at 100° C., calculated from torque measured by the rubber process analysis, is G′ d , G′ d is ≤100 kPa.

3. The multiblock copolymer of claim 1 , wherein, provided that difference between storage modulus G′ at 130° C. and storage modulus G′ at 100° C., calculated from torque measured by the rubber process analysis, is G′ d , 20 kPa≤G′ d ≤100 kPa.

4. The multiblock copolymer of claim 1 , wherein, provided that difference between storage modulus G′ at 130° C. and storage modulus G′ at 100° C., calculated from torque measured by the rubber process analysis, is G′ d , 20 kPa≤G′ d ≤50 kPa.

5. A rubber composition, having as a rubber component the multiblock copolymer of claim 1 .

6. A tire, having the rubber composition of claim 5 .

Assignees

• Bridgestone Corp

Inventors

• Tardif Olivier
• Oishi Shigeki

Classifications

• C08F4/545

  rare earths being present, e.g. triethylaluminium + neodymium octanoate · CPC title

• C08F293/00

  Macromolecular compounds obtained by polymerisation on to a macromolecule having groups capable of inducing the formation of new polymer chains bound exclusively at one or both ends of the starting macromolecule (on to polymers modified by introduction of unsaturated end groups C08F290/02) · CPC title

• C08K3/04

  Carbon · CPC title

• C08F297/06 Primary

  using a catalyst of the coordination type · CPC title

• B60C1/00 Primary

  Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition · CPC title