Claims
- 1. A curable elastomer composition consisting essentially of:
- (a) a recycle component of an at least partially vulcanized fluorinated elastomer; and optionally, an unvulcanized fluoroelastomer gum, and
- (b) an amount of a cure-enhancing additive system that is effective to improve the maximum torque during cure of a composition according to this claim over the maximum torque during cure of a similar composition that does not have the additive system, the additive system consisting essentially of
- (i) a cure enhancing additive selected from the group consisting of a fluoroaliphatic sulfonamide, a free radical scavenger, and a mixture of the two,
- (ii) optionally a crosslinking agent for a fluoroelastomer gum, and,
- (iii) optionally an accelerator.
- 2. The composition according to claim 1 wherein the the recycle component is the at least partially vulcanized fluoroelastomer.
- 3. The composition according to claim 1 wherein the recycle component is a mixture of the unvulcanized fluorinated elastomer gum, and the at least partially vulcanized fluoroelastomer.
- 4. The composition according to claim 1 wherein the cure-enhancing additive system includes the crosslinking agent.
- 5. The composition according to claim 1 wherein the cure-enhancing additive system includes the accelerator.
- 6. The composition according to claim 1 further consisting essentially of a processing aid.
- 7. The composition according to claim 1 wherein
- (a) the cure-enhancing additive is a mixture of a fluoroaliphatic sulfonamide and a free radical scavenger;
- (b) the crosslinking agent is selected from the group consisting of organic peroxides, inorganic peroxides, polyhydroxy compounds, organic polyamines, fluoroaliphatic polyols, allyl ethers of polyhydroxy compounds, and allyl carbonates of polyhydroxy compounds; and
- (c) the accelerator consists essentially of an organo-onium compound.
- 8. The composition according to claim 7 wherein the cure-enhancing additive is a free radical scavenger selected from the group consisting of phenol compounds, phosphite compounds, thioester compounds, and amine compounds.
- 9. A composition useful to recycle cured fluoroelastomer materials consisting essentially of:
- (a) a recycle component comprising an at least partially vulcanized fluoroelastomer,
- (b) an amount of an additive system that is effective to improve the maximum torque during cure of a composition according to this claim over the maximum torque during cure of a similar composition that does not contain the additive system, the additive system consisting essentially of
- (i) a cure-enhancing additive selected from the group consisting of fluoroaliphatic sulfonamide, a free radical scavenger, and a mixture of the two,
- (ii) a curative for a fluoroelastomer gum, and
- (iii) an organo-onium accelerator.
- 10. A composition according to claim 9 further consisting essentially of a virgin fluoroelastomer gum.
- 11. An article comprising the crosslinked composition of claim 9.
- 12. A method of recycling an at least partially vulcanized fluorinated elastomer consisting essentially of the steps of:
- (a) providing a quantity of an at least partially vulcanized fluorinated elastomer; and an additive system comprising essentially of
- (i) at least one cure-enhancing additive selected from the group consisting of a fluoroaliphatic sulfonamide, a free radical scavenger, and a mixture of the two,
- (ii) at least one curative, and,
- (iii) optionally at least one accelerator,
- (b) refining the at least partially vulcanized fluoroelastomer by mixing under conditions which break the crosslinks and reduce the molecular weight in order to form a continuous mass,
- (c) blending the additive system with the at least partially vulcanized fluoroelastomer, optionally while the at least partially vulcanized fluoroelastomer is being refined, and
- (d) curing the resulting composition.
- 13. A method according to claim 12 wherein refining the at least partially vulcanized fluoroelastomer occurs in the presence of a virgin fluoroelastomer gum.
- 14. A curable fluoroelastomer composition consisting of:
- (a) a virgin fluoroelastomer gum, and
- (b) an amount of a cure-enhancing additive system that is effective to improve the maximum torque during cure of a composition according to this claim over the maximum torque during cure of a similar composition that does not contain the additive system, the additive system consisting essentially of
- (i) a cure-enhancing additive selected from the group consisting of a fluoroaliphatic sulfonamide, a free radical scavenger, and a mixture of the two,
- (ii) a curative, and
- (iii) an accelerator, and
- (c) a recycle component of an at least partially vulcanized fluorinated elastomer.
- 15. A curable composition useful in recycling at least partially cured fluoroelastomer materials into uncured fluoroelastomer materials consisting essentially of:
- (a) a recycle component of an at least partially vulcanized fluoroelastomer, and, optionally an unvulcanized fluoroelastomer gum,
- (b) from 1 to 1000 millimoles of a cure-enhancing additive system per 100 parts of the recycle component wherein the cure-enhancing additive system consists essentially of
- (i) a cure-enhancing additive selected from the group consisting of a fluoroaliphatic sulfonamide, a free radical scavenger, and a mixture of the two,
- (ii) optionally a crosslinking agent for a fluoroelastomer gum, and,
- (iii) optionally an accelerator.
- 16. The composition according to claim 15 wherein the cure-enhancing additive system consists essentially of from about
- (a) 1 to 45 weight percent of the cure-enhancing additive,
- (b) 1 to 75 weight percent of the crosslinking agent, and
- (c) 1 to 40 weight percent of the accelerator.
- 17. The composition according to claim 15 wherein the cure-enhancing additive consists essentially of C.sub.8 F.sub.17 SO.sub.2 NHCH.sub.3.
- 18. The composition according to claim 15 wherein the crosslinking agent consists essentially of HO--.0.--C(CF.sub.3).sub.2 --.0.--OH (Bisphenol AF).
- 19. The composition according to claim 15 wherein the accelerator consists essentially of the reaction product of equimolar quantities of triphenyl benzyl phosphonium chloride and the sodium salt of HO--.0.--C(CF.sub.3).sub.2 --.0.--OH (Bisphenol AF).
- 20. A curable composition useful in recycling cured fluoroelastomer materials consisting of:
- (a) an unvulcanized fluoroelastomer gum,
- (b) an at least partially vulcanized fluorinated elastomer, and
- (c) an additive system that consists essentially of
- (i) at least one cure-enhancing additive selected from the group consisting of a fluoroaliphatic sulfonamide, a free radical scavenger, and a mixture of the two
- (ii) at least one curative, and,
- (iii) optionally at least one accelerator.
- 21. A curable fluoroelastomer composition useful in recycling cured fluoroelastomer materials comprising:
- (a) an at least partially vulcanized fluorinated elastomer, and
- (b) optionally an unvulcanized fluoroelastomer gum, and
- (c) an additive system that consists essentially of
- (i) at least one cure-enhancing additive, and selected from the group consisting of a fluoroaliphatic sulfonamide, a free radical scavenger, and a mixture of the two
- (ii) optionally at least one curative, and,
- (iii) optionally at least one accelerator
- wherein after curing, the fluoroelastomer composition has improved compression set as compared to similar fluoroelastomer composition that does not contain the additive system.
Parent Case Info
This application claims priority from U.S. Provisional Application 60/036,230, filed Mar. 12, 1997.
US Referenced Citations (25)
Foreign Referenced Citations (1)
Number |
Date |
Country |
120462A1 |
Oct 1984 |
EPX |