Patent US4533711A successfully refreshed from Google Patents.
US4533711A
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Polybutadiene rubber compositions having improved green strength
Assignee: Bridgestone Corp
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Filing: 1983-09-07
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Granted: 1985-08-06
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Expires: 2003-09-07
Abstract
Abstract A polybutadiene rubber composition having an improved green strength is disclosed, which comprises a polybutadiene having a content of cis-1,4 bond of at least 70%, an average chain length of 1,4-bond of 110˜450 and a molecular weight distribution represented by a ratio of weight-average molecular weight to number-average molecular weight of not less than 5.0.
Inventors
- 👤 Yasumasa Takeuchi
- 👤 Mitsuhiko Sakakibara
- 👤 Nobuo Tagata
- 👤 Masaki Ogawa
- 👤 Yasushi Hirata
- 👤 Shigeru Tomihira
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:50
CPC Classifications
C; C08; C08F; C08F136/00; C08F136/02; C08F136/04; C08F136/06
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
80 words
A polybutadiene rubber composition having an improved green strength, which comprises a polybutadiene having a content of cis-1,4 bond of at least 70%, an average chain length of 1,4-bond of 110˜450, a molecular weight distribution represented by a ratio of weight-average molecular weight (Mw) to number-averge molecular weight (Mn) of not less than 5.0 and containing at least 1% by weight of a component having a molecular weight of not less than 25,000,000 as polystyrene measured by gel permeation chromatograph.
Claim 2
Dependent Claim
80 words
A polybutadiene rubber composition having an improved green strength, which comprises a polybutadiene having a content of cis-1,4 bond of at least 70%, an average chain length of 1,4-bond of 110˜450, a molecular weight distribution represented by a ratio of weight-average molecular weight (Mw) to number-averge molecular weight (Mn) of not less than 5.0 and containing at least 1% by weight of a component having a molecular weight of not less than 25,000,000 as polystyrene measured by gel permeation chromatograph.
Claim 3
Dependent Claim
195 words
A polybutadiene rubber composition according to claim 1, wherein said polybutadiene is produced by polymerizing 1,3-butadiene in the presence of a catalyst system containing the following compounds (I)-(III) as an essential ingredient: (I) a compound of a lanthanum series rare earth element having an atomic number of 57˜71; (II) an organoaluminum compound represented by a general formula of AlR 1 R 2 R 3 , wherein R 1 , R 2 and R 3 are the same or different and represent a hydrocarbon residue having a carbon number of 1˜8, respectively; and (III) a halogenated aluminum compound represented by a general formula of AlX n R 3-n , wherein X is a halogen atom, R is a hydrocarbon residue having a carbon number of 1˜8 and n is 1 to 3, until a degree of conversion of 1,3-butadiene reaches at least 3%, and then adding at least one compound selected from organoaluminum hydrides represented by a general formula of AlH m R 3-m , wherein R is a hydrocarbon residue having a carbon number of 1˜8 and m is 1 or 2, and aromatic hydrocarbons containing an active hydrogen as a modifier to complete polymerization.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-08-05 | 1989-02-04 | 1989-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-05 | 1993-02-04 | 1993-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-05 | 1997-02-04 | 1997-08-06 | $7700.00 | Window Closed / Lapsed |