Hydrogenated block copolymer and composition comprising same

Patent metadata

Field	Value
Publication number	US-9718953-B2
Application number	US-201615058519-A
Country	US
Kind code	B2
Filing date	Mar 2, 2016
Priority date	Feb 14, 2011
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

A thermoplastic elastomer composition includes a hydrogenated block copolymer, which is obtained by hydrogenating a block copolymer having two or more polymer blocks (a) each containing a structural unit derived from an aromatic vinyl compound and one or more polymer blocks (b) each containing structural units derived from isoprene and 1,3-butadiene, a thermoplastic resin, and a rubber softener. The hydrogenated block copolymer has a crystallization peak temperature (Tc) of −3 to 15° C.

First claim

The invention claimed is:

1. A thermoplastic elastomer composition, comprising:
a hydrogenated block copolymer (A);
a thermoplastic resin (B); and
a rubber softener (C);
wherein:
the hydrogenated block copolymer is obtained by hydrogenating a block copolymer having:
two or more polymer blocks (a) each containing a structural unit derived from an aromatic vinyl compound; and
one or more polymer blocks (b) each containing structural units derived from isoprene and 1,3-butadiene;

the hydrogenated block copolymer has a crystallization peak temperature (Tc) of 2 to 15° C.;
the crystallization peak temperature (Tc) is a peak top temperature of an exothermic peak observed when a temperature of a sample of the hydrogenated block copolymer is increased from 30° C. to 150° C. at a rate of 10° C./min and then the sample is cooled to −100° C. at a rate of 10° C./min, the peak top temperature being measured with a differential scanning calorimeter (DSC); and
a content of the polymer blocks (a) in the hydrogenated block copolymer is 20 to 34 mass %.

2. The thermoplastic elastomer composition according to claim 1 , wherein a content of the polymer blocks (a) in the hydrogenated block copolymer is 25 to 33 mass %.

3. The thermoplastic elastomer composition according to claim 1 , wherein a glass transition temperature (Tg) of the hydrogenated block copolymer (A) is −60 to −30° C.

4. The thermoplastic elastomer composition according to claim 1 , wherein a glass transition temperature (Tg) of the hydrogenated block copolymer (A) is −55 to −45° C.

5. The thermoplastic elastomer composition according to claim 1 , wherein a crystal melting heat quantity of the hydrogenated block copolymer (A) is 15 to 30 mJ/mg.

6. The thermoplastic elastomer composition according to claim 1 , wherein a crystal melting heat quantity of the hydrogenated block copolymer (A) is 17 to 25 mJ/mg.

7. The thermoplastic elastomer composition according to claim 1 , wherein a tensile strength of the hydrogenated block copolymer (A) is 40 to 45 MPa.

8. The thermoplastic elastomer composition according to claim 1 , wherein an elastic recovery of the hydrogenated block copolymer (A) is 0.3 to 0.5.

9. A thermoplastic elastomer composition, comprising:
a hydrogenated block copolymer (A);
a thermoplastic resin (B); and
a rubber softener (C);
wherein:
the composition comprises:
50 to 80 parts by mass of the hydrogenated block copolymer (A) based on 100 parts by weight of (A), (B), and (C);
5 to 30 parts by mass of the thermoplastic resin (B) based on 100 parts by weight of (A), (B), and (C); and
10 to 45 parts by mass of the rubber softener (C) based on 100 parts by weight of (A), (B), and (C);

the hydrogenated block copolymer is obtained by hydrogenating a block copolymer having:
two or more polymer blocks (a) each containing a structural unit derived from an aromatic vinyl compound; and
one or more polymer blocks (b) each containing structural units derived from isoprene and 1,3-butadiene;

the hydrogenated block copolymer has a crystallization peak temperature (Tc) of −3 to 15° C.;
the crystallization peak temperature (Tc) is a peak top temperature of an exothermic peak observed when a temperature of a sample of the hydrogenated block copolymer is increased from 30° C. to 150° C. at a rate of 10° C./min and then the sample is cooled to −100° C. at a rate of 10° C./min, the peak top temperature being measured with a differential scanning calorimeter (DSC); and
a content of the polymer blocks (a) in the hydrogenated block copolymer is 20 to 34 mass %.

10. The thermoplastic elastomer composition according to claim 9 , wherein the thermoplastic resin (B) comprises a polystyrene-based resin (B′).

11. The thermoplastic elastomer composition according to claim 1 , wherein the thermoplastic resin (B) comprises a polystyrene-based resin (B′).

12. The thermoplastic elastomer composition according to claim 1 , wherein the thermoplastic resin (B) comprises at least one member selected from the group consisting of a polyethylene-based resin, a polypropylene-based resin, an acrylic resin, a polyphenylene ether-based resin, a polycarbonate-based resin, a polyvinyl acetate-based resin, a polyester-based resin, a polyamide-based resin, and a polyvinyl chloride-based resin.

13. The thermoplastic elastomer composition according to claim 1 , wherein the rubber softener (C) comprises at least one member selected from the group consisting of a paraffin-based process oil, a naphthene-based process oil, peanut oil, rosin, a phosphoric acid ester, a low-molecular-weight polyethylene glycol, liquid paraffin, a low-molecular-weight polyethylene, an ethylene-α-olefin co-oligomer, liquid polybutene, liquid polyisoprene, hydrogenated liquid polyisoprene, liquid polybutadiene, and hydrogenated liquid polybutadiene.

14. The thermoplastic elastomer composition according to claim 1 , wherein:
the crystallization peak temperature of the hydrogenated block copolymer is 2 to 13° C.;
an amount of 1,4-bonds in the hydrogenated block copolymer formed from the structural units derived from isoprene and butadiene of 90 to 95%; and
96 to 100% of carbon-carbon double bonds in the hydrogenated block copolymer derived from isoprene and butadiene are hydrogenated.

15. The thermoplastic elastomer composition according to claim 9 , wherein:
the crystallization peak temperature of the hydrogenated block copolymer is 2 to 13° C.;
an amount of 1,4-bonds in the hydrogenated block copolymer formed form the structural units derived from isoprene and butadiene of 90 to 95%; and
96 to 100% of carbon-carbon double bonds in the hydrogenated block copolymer derived from isoprene and butadiene are hydrogenated.

16. The thermoplastic elastomer composition according to claim 1 , wherein the crystallization peak temperature of the hydrogenated block copolymer is 5 to 13° C.

17. The thermoplastic elastomer composition according to claim 9 , wherein the crystallization peak temperature of the hydrogenated block copolymer is 5 to 13° C.

Assignees

• Kuraray Co

Inventors

• Jogo Yosuke
• Shachi Kenji
• Moriguchi Nobuhiro

Classifications

• C08L53/025 Primary

  modified · CPC title

• C08F297/046

  polymerising vinyl aromatic monomers and isoprene, optionally with other conjugated dienes · 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

• C08L25/08

  Copolymers of styrene (C08L29/08, C08L35/06, C08L55/02 take precedence) · CPC title

• C08L91/00

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