Claims
- 1. A rubber composition having a high modulus and excellent processability which is comprised of a blend of (1) at least one elastomer selected from the group consisting of polybutadiene rubber, styrene-butadiene rubber, synthetic polyisoprene rubber, natural rubber, isoprene-butadiene rubber, isoprene-butadiene-styrene rubber, nitrile rubber, carboxylated nitrile rubber, and EPDM rubber, (2) at least one thermotropic liquid crystalline polymer containing an aliphatic spacer which has a crystalline to nematic transition at a temperature which is within the range of about 110.degree. C. to about 220.degree. C., wherein the thermotropic liquid crystalline polymer is comprised of repeat units which are derived from hydroquinone, p-hydroxylbenzoic acid, and an aliphatic dicarboxylic acid having the structural formula HOOC--CH.sub.2 --COOH wherein n represents an integer from about 4 to about 8, and (3) carbon black.
- 2. A rubber composition as specified in claim 1 wherein the elastomer is styrene-butadiene rubber.
- 3. A rubber composition as specified in claim 1 wherein from about 4 to about 30 phr of at least one thermotropic liquid crystalline polymer is present.
- 4. A rubber composition as specified in claim 1 wherein from about 5 phr to about 15 phr of at least one thermotropic liquid crystalline polymer is present.
- 5. A rubber composition as specified in claim 1 wherein the thermotropic liquid crystalline polymer has a crystalline to nematic transition at a temperature which is within the range of about 110.degree. C. to about 180.degree. C.
- 6. A rubber composition as specified in claim 1 wherein the aliphatic dicarboxylic acid is azelaic acid.
- 7. A rubber composition as specified in claim 1 wherein the aliphatic dicarboxylic acid is pimelic acid.
- 8. A rubber composition as specified in claim 1 wherein the elastomer is natural rubber.
- 9. A rubber composition as specified in claim 1 wherein the rubber composition was prepared by mixing the thermotropic liquid crystalline polymer with the elastomer in the absence of a curative.
- 10. A rubber composition as specified in claim 1 wherein said rubber composition was prepared by mixing a powder of the thermotropic liquid crystalline polymer throughout the elastomer.
- 11. A rubber composition as specified in claim 9 wherein the liquid crystalline polymer was in the form of a powder during the mixing procedure.
- 12. A rubber composition as specified in claim 1 which further comprises carbon black.
- 13. A rubber composition as specified in claim 1 wherein said rubber composition is vulcanized.
- 14. A rubber composition specified in claim 1 which further comprises sulfur or a sulfur containing compound.
- 15. A rubber composition as specified in claim 14 which further comprises at least one accelerator.
- 16. A rubber composition as specified in claim 1 wherein said elastomer is polybutadiene.
- 17. A rubber composition as specified in claim 1 wherein the aliphatic dicarboxylic acid is suberic acid.
- 18. A rubber composition as specified in claim 1 wherein the aliphatic dicarboxylic acid is sebacic acid.
Parent Case Info
This is a continuation-in-part of U.S. patent application Ser. No. 07/248,849, filed on Sep. 26, 1988 (now abandoned).
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|
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Country |
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EPX |
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JPX |
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Non-Patent Literature Citations (1)
Entry |
Lorenzo et al. Polymer Preprints, 29(1), 1988, pp. 488-490. |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
248849 |
Sep 1988 |
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