Claims
- 1. A vulcanizable rubber composition which comprises a vulcanizable rubber, sulfur or sulfur donor, at least one accelerator, and a zinc salt of a partial ester of a polycarboxylic acid, the partial ester being selected from the semi-ester of an aliphatic C.sub.4 -C.sub.10 dicarboxylic acid, tetrahydrophthalic acid or hexahydrophthalic acid, or a C.sub.8 -C.sub.14 benzene dicarboxylic acid or from the diester of an aliphatic C.sub.6 -C.sub.12 tricarboxylic acid, in an amount effective to improve the compression set and hot air aging properties of the composition when vulcanized.
- 2. The composition of claim 1, wherein the rubber is selected from low C.dbd.C double bond content rubber, natural rubber, polychloroprene, polybutadiene, polyisoprene, styrene/butadiene copolymers, butadiene/olefin copolymers, acrylonitrile/diene copolymers or acrylic ester/diene copolymers.
- 3. The composition of claim 1, wherein the low C.dbd.C bond content rubber is EPDM rubber, butyl rubber, or hydrogenated nitrile rubber.
- 4. The composition of claim 1 which contains a thiuramic and optionally a thiazole accelerator.
- 5. The composition of claim 1, which contains as rubber a rubber having a low C.dbd.C double bond content, from 0.2 to 1% sulfur, from 1 to 3.5% of thiuramic accelerator, optionally from 0.2 to 1% of thiazole accelerator, and from 0.1 to 8% of said zinc salt of a partial ester of a polycarboxylic acid, the percentages being based on weight of rubber.
- 6. The composition of claim 5, wherein the partial ester is the esterification product of adipic acid, glutaric acid or succinic acid with an alcohol having 1-18 C atoms.
- 7. The composition of claim 6, containing as salt of a partial ester the zinc salt of succinic acid octyl ester.
- 8. The composition of claim 1, wherein the vulcanizable rubber is selected from the group consisting of natural rubber, polychloroprene, polybutadiene, polyisoprene, styrene/butadiene copolymers, butadiene/olefin copolymers, acrylonitrile/diene copolymers or acrylic ester/diene copolymers, and which contains 0.1 to 2% by weight sulfur, from 1 to 4.5% by weight vulcanization accelerators, and from 0.5 to 6% by weight of said zinc salt of a partial ester of a polycarboxylic acid, the percentages being based on weight of rubber.
- 9. The composition of claim 8 wherein the acid component of the partial ester is an aliphatic dicarboxylic acid.
- 10. The composition of claim 8, wherein the salts are zinc salts of succinic acid monooctyl ester, or of glutaric acid monobutyl ester or monooctyl ester.
Priority Claims (2)
Number |
Date |
Country |
Kind |
40 31 566.5 |
Oct 1990 |
DEX |
|
42 00 907.3 |
Jan 1992 |
DEX |
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Parent Case Info
This application is a continuation-in-part of Ser. No. 002,117, filed Jan. 4, 1993 now abandoned, which is a continuation of Ser. No. 763,996, filed Sep. 23, 1991, and is also a continuation-in-part of Ser. No. 001,566, filed Jan. 6, 1993now abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (4)
Number |
Date |
Country |
0386499 |
Sep 1990 |
EPX |
0479083 |
Apr 1992 |
EPX |
1092175 |
Nov 1967 |
GBX |
1302360 |
Jan 1973 |
GBX |
Continuations (1)
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Number |
Date |
Country |
Parent |
763996 |
Sep 1991 |
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
2117 |
Jan 1993 |
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