Granted Patent B2

US 9,371,426 · App. 12/329,676 · Granted Jun 21, 2016

Abstract

Claims (25)

1. A crosslinked organic polymer:

the crosslinked organic polymer being at a temperature below its glass transition temperature; where the crosslinked organic polymer is a polyacetal, a polyacrylic, a polycarbonate, a polyester, a polyamide, a polyamideimide, a polyarylate, a polyarylsulfone, a polyethersulfone, a polyphenylene sulfide, a polysulfone, a polyimide, a polyetherimide, a polyetherketone, a polyether etherketone, a polyether ketone ketone, a polybenzoxazole, a polyphthalide, a polyanhydride, a polyvinyl ether, a polyvinyl thioether, a polyvinyl alcohol, a polyvinyl ketone, a polyvinyl nitrile, a polyvinyl ester, a polysulfonate, a polysulfide, a polythioester, a polysulfone, a polysulfonamide, a polyurea, a polyphosphazene, a polysilazane, or a combination thereof;

where the polyamide is polypyrrolidone, polycaprolactam, polytetramethylene adipamide, polycapryllactam, polyhexamethylene adipamide, polyundecanolactam, polydodecanolactam, polyhexamethylene azelaiamide, polyhexamethylene sebacamide, polyhexamethylene isophthalamide, polyhexamethylene terephthalamide, polyphthalamide, or a combination thereof;

wherein a composition comprising the crosslinked organic polymer has a coefficient of friction that is about 10% to about 70% greater than a coefficient of friction for a composition comprising the same organic polymer that is not crosslinked; and wherein a composition comprising the crosslinked organic polymer has a lower K factor than a K factor of a composition comprising the same organic polymer that is not crosslinked; the coefficient of friction and the K factor being measured in a thrust washer apparatus as per ASTM D-3702, where the counter stationary surface in the thrust washer apparatus comprises carbon steel having a Rockwell C hardness of 18 to 22 and a 12 to 16 micro-inch surface finish.

2. The crosslinked organic polymer of claim 1 , where the crosslinked organic polymer is the reaction product of an organic polymer with a crosslinking agent.

3. The crosslinked organic polymer of claim 2 , where the crosslinking agent is a cyanurate crosslinking agent, an isocyanate crosslinking agent, a polyaldehyde crosslinking agent, a phosphine crosslinking agent, an epoxy crosslinking agent, or a combination thereof.

4. The crosslinked organic polymer of claim 1 , where the crosslinked organic polymer is obtained by exposing an organic polymer to radiation.

5. The crosslinked organic polymer of claim 4 , where the radiation is xray radiation, electron beam radiation, gamma radiation, beta radiation, ultraviolet radiation, alpha radiation, or a combination thereof.

6. The crosslinked organic polymer of claim 4 , where a radiation dosage is about 10 to about 500 kiloGrays per unit cross-sectional area of about 100 square micrometers to about 900 square centimeters.

7. The crosslinked organic polymer of claim 1 , where the crosslinked organic polymer comprises a gradient in crosslink density.

8. The crosslinked organic polymer of claim 1 , wherein a composition comprising the crosslinked organic polymer comprises a gradient in the coefficient of friction.

9. The crosslinked organic polymer of claim 1 , wherein a composition comprising the crosslinked organic polymer comprises a gradient in the K factor across a cross-sectional area.

10. The crosslinked organic polymer of claim 1 , wherein a composition comprising the crosslinked organic polymer has a K factor of about 1,000.10 −3 inch 3 /cal or less.

11. An article comprising the composition comprising the crosslinked organic polymer of claim 1 .

12. A crosslinked organic polymer:

where the crosslinked organic polymer is a polyamide being at a temperature below its glass transition temperature, where the polyamide is polypyrrolidone, polycaprolactam, polytetramethylene adipamide, polycapryllactam, polyhexamethylene adipamide, polyundecanolactam, polydodecanolactam, polyhexamethylene azelaiamide, polyhexamethylene sebacamide, polyhexamethylene isophthalamide, polyhexamethylene terephthalamide, polyphthalamide, or a combination thereof;

wherein a composition comprising the crosslinked organic polymer has a coefficient of friction that is about 10% to about 70% greater than a coefficient of friction for a composition comprising the same organic polymer that is not crosslinked; and wherein a composition comprising the crosslinked organic polymer has a lower K factor than a K factor of a composition comprising the same organic polymer that is not crosslinked; the coefficient of friction and the K factor being measured in a thrust washer apparatus as per ASTM D-3702.

13. The crosslinked organic polymer of claim 12 , where the crosslinked organic polymer comprises a gradient in crosslink density.

14. The crosslinked organic polymer of claim 12 , wherein a composition comprising the crosslinked organic polymer comprises a gradient in coefficient of friction.

15. The crosslinked organic polymer of claim 12 , wherein a composition comprising the crosslinked organic polymer comprises a gradient in K factor across a cross-sectional area.

16. An article comprising the composition comprising the crosslinked organic polymer of claim 12 .

17. The article of claim 11 , where the article is a gear, a cam, a worm wheel, or a piston rod.

18. The article of claim 11 , where the article is a component in a machine.

19. The article of claim 16 , where the article is a gear, a cam, a worm wheel, or a piston rod.

20. The article of claim 16 , where the article is a component in a machine.

Assignments (8)