Claims
- 1. An isoprene-butadiene copolymer rubber having improved processing properties which comprises a microstructure of the butadiene portion having from 70% to 90% of trans-1,4 linkage and from 2% to 8% of vinyl linkage, an isoprene content of from 3 to 25 wt %, and a styrene content of from 0 to 30 wt %, said copolymer rubber having a Mooney Viscosity of from 30 to 150, and a molecular weight distribution, Mw/Mn of from 1.2 to 3.5, said rubber, in the unelongated state, not exhibiting a melting point measured by the differential scanning calorimeter analysis method.
- 2. The isoprene-butadiene copolymer rubber as claimed in claim 1, wherein the total content of isoprene and styrene is not more than 25 wt %.
- 3. The isoprene-butadiene copolymer rubber as claimed in claim 1 or 2, wherein the isoprene is substantially randomly copolymerized.
- 4. The isoprene-butadiene copolymer rubber as claimed in claim 1 or 2, wherein the isoprene is substantially block copolymerized.
Priority Claims (1)
Number |
Date |
Country |
Kind |
53-100006 |
Aug 1978 |
JPX |
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Parent Case Info
This application is a continuation, copending application Ser. No. 61,248, filed on July 27, 1979, now abandoned.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
3992561 |
Hargis et al. |
Nov 1976 |
|
4048427 |
Hargis et al. |
Sep 1977 |
|
4080492 |
DeZarauz |
Mar 1978 |
|
Foreign Referenced Citations (1)
Number |
Date |
Country |
1525381 |
Sep 1978 |
GBX |
Continuations (1)
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Number |
Date |
Country |
Parent |
61248 |
Jul 1979 |
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