Polyurea-urethane cord treatment for power transmission belt and belt

Patent metadata

Field	Value
Publication number	US-11111342-B2
Application number	US-201815941672-A
Country	US
Kind code	B2
Filing date	Mar 30, 2018
Priority date	Dec 1, 2009
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

A belt with a tensile cord embedded in an elastomeric body, having a polyurea-urethane adhesive composition impregnating the cord and coating the fibers. The composition is reaction product of a polyurethane prepolymer and a diamine curative. The prepolymer is a reaction product of a compact, symmetric diisocyanate and a polyester, polyether, or polycarbonate polyol. The belt body may be of cast polyurethane, vulcanized rubber, or thermoplastic elastomer. The cord may have an adhesive overcoat.

First claim

What is claimed is:

1. A power transmission belt comprising: an elastomeric body, and a tensile cord embedded in the elastomeric body;
with the tensile cord impregnated with a polyurea-urethane composition different from said elastomeric body, said said polyurea-urethane composition consisting of the polyurea reaction product of:
a polyurethane prepolymer; and
a curative selected from the group consisting of diamines and water;

said tensile cord obtained by impregnation with said polyurethane prepolymer and said curative, followed by reaction to form said polyurea reaction product, optionally in the presence of non-reactive ingredients.

2. The belt of claim 1 wherein said polyurea-urethane composition is a crosslinked polyurea-urethane composition.

3. The belt of claim 2 wherein said tensile cord is a twisted tensile cord and said curative is a diamine.

4. The belt of claim 1 wherein said prepolymer comprises the reaction product of a diisocyanate and one or more polyols selected from the group consisting of polyester polyols, polycarbonate polyols and polyether polyols.

5. The belt of claim 4 wherein said diisocyanate is selected from the group consisting of para-phenylene diisocyanate, toluene diisocyanate, and 4,4′-methylene diphenyl diisocyanate.

6. The belt of claim 5 wherein said one or more polyols is selected from the group consisting of polyether polyols.

7. The belt of claim 6 wherein said tensile cord comprises a yarn comprising a plurality of carbon fibers with interstices between said carbon fibers, and wherein said composition impregnates from 20% to 100% of the volume of said interstices and coats said carbon fibers.

8. The belt of claim 1 wherein said prepolymer comprises the reaction product of para-phenylene diisocyanate and a polyether polyol.

9. The belt of claim 8 wherein said curative is 4,4′-methylenebis(3-chloro-2,6-diethylaniline).

10. The belt of claim 9 wherein said elastomeric body comprises cast polyurethane elastomer, and said elastomer is in intimate contact with said polyurea-urethane composition.

11. The belt of claim 10 wherein said tensile cord comprises a yarn comprising a plurality of carbon fibers with interstices between said carbon fibers, and wherein said composition impregnates from 20% to 99% of the volume of said interstices and coats said carbon fibers; and wherein said elastomer impregnates at least a portion of the remainder of said interstices.

12. The belt of claim 1 wherein said elastomeric body comprises vulcanized rubber.

13. The belt of claim 1 wherein said elastomeric body comprises a thermoplastic elastomer and said elastomer is in intimate contact with said polyurea-urethane composition.

14. The belt of claim 13 wherein said elastomer is a thermoplastic polyurethane.

15. The belt of claim 1 wherein the polyurethane prepolymer has isocyanate end groups that are blocked with a blocking agent.

16. The belt of claim 4 wherein said diisocyanate comprises para-phenylene diisocyanate, toluene diisocyanate, or both, and wherein said polyol comprises a polyether polyol.

17. The belt of claim 16 , wherein said polyether polyol comprises polytetramethylene ether glycol.

18. The belt of claim 4 , wherein said diisocyanate comprises isophorone diisocyanate, hexamethylene diisocyanate, or both, and wherein said polyol comprises a polyether polyol.

19. The belt of claim 18 , wherein said polyether polyol comprises polytetramethylene ether glycol.

Assignees

• Gates Corp

Inventors

• Duke Jr Joseph R
• Knox John Graeme

Classifications

• C08J5/046 Primary

  with synthetic macromolecular fibrous material · CPC title

• Y10T156/10

  Methods of surface bonding and/or assembly therefor · CPC title

• C09J175/04

  Polyurethanes · CPC title

• C08J5/042

  with carbon fibres · CPC title

• D06M15/564

  Polyureas, polyurethanes or other polymers having ureide or urethane links; Precondensation products forming them · CPC title