Rubber composition, vulcanizate, molded article, and transmission belt

Abstract

[Problem] To provide a rubber composition or the like with which it is possible to produce a molded article (especially a transmission belt) having high hardness and high tensile strength. [Solution] One aspect of the present invention provides a rubber composition comprising 100 parts by mass of a sulfur-modified chloroprene rubber, 20-70 parts by mass of silica, and a coupling agent having a bonding group capable of bonding with the sulfur-modified chloroprene rubber.

Claims

1. A rubber composition comprising 100 parts by mass of sulfur-modified chloroprene rubber, 20 to 70 parts by mass of silica, and a coupling agent having a binding group capable of binding to the sulfur-modified chloroprene rubber.

2. In the rubber composition according to claim 1, the BET specific surface area of ​​the silica is 100 m². ２ / g or more 300m ２ A rubber composition having a weight of less than or equal to / g.

3. The rubber composition according to claim 2, wherein the binding group is at least one selected from the group consisting of oxygen-containing functional groups and nitrogen-containing functional groups.

4. The rubber composition according to claim 2, wherein the coupling agent contains at least one selected from the group consisting of (meth)acrylic coupling agents, epoxy coupling agents, and amine coupling agents.

5. The rubber composition according to claim 1, wherein the content of the coupling agent is 0.5 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the sulfur-modified chloroprene rubber.

6. The rubber composition according to claim 1, further comprising an aggregation inhibitor for suppressing the aggregation of silica.

7. The rubber composition according to claim 6, wherein the flocculation inhibitor contains polyalkylene glycol.

8. The rubber composition according to claim 6, wherein the content of the flocculation inhibitor is 0.5 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the sulfur-modified chloroprene rubber.

9. A rubber composition according to claim 1, further comprising a vulcanization retarder.

10. The rubber composition according to claim 9, wherein the vulcanization retarder contains a compound having a benzothiazole skeleton.

11. The rubber composition according to claim 9, wherein the content of the vulcanization retarder is 0.1 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the sulfur-modified chloroprene rubber.

12. A rubber composition according to claim 1, further comprising an acid acceptor.

13. The rubber composition according to claim 12, wherein the acid acceptor contains at least one selected from the group consisting of layered double hydroxides, metal hydroxides, and metal oxides.

14. The rubber composition according to claim 12, wherein the content of the acid acceptor is 2 parts by mass or more and 20 parts by mass or less per 100 parts by mass of the sulfur-modified chloroprene rubber.

15. A rubber composition according to claim 1, further comprising a cocrosslinking agent.

16. The rubber composition according to claim 15, wherein the cocrosslinking agent contains a maleimide compound.

17. The rubber composition according to claim 15, wherein the content of the cocrosslinking agent is 0.5 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the sulfur-modified chloroprene rubber.

18. A vulcanized product, the vulcanized product of the rubber composition according to any one of claims 1 to 17.

19. A molded article comprising the vulcanized product described in claim 18.

20. A power transmission belt comprising the molded body described in claim 19.

Images