US3928490A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Block polymers of polysiloxanes and polybutadiene
Assignee: Bridgestone Firestone Inc
•
Filing: 1973-08-16
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Granted: 1975-12-23
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Expires: 1993-08-16
Abstract
Abstract Block polymers are produced by polymerizing butadiene and joining to polysiloxane to make a copolymer with alternating blocks of polybutadiene and polysiloxane. The products are useful for the manufacture of gaskets, hose, belts, and other products designed for high-temperature use.
Inventors
- 👤 William L Hergenrother
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:50
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/42; C08G77/442
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
109 words
THE METHOD OF PRODUCING A LINEAR ALTERNATING BLOCK COPOLYMER COMPOSED OF (A) 1 TO 80 PER CENT BY WEIGHT OF A POLYBUTADIENE WITH A VINYL CONTENT OF AT LEAST 60 PER CNE WEIGHT AND (B) 20 TO 99 PER CENT BY WEIGHT OF A LINEAR POLYSILOXANE HAVING THE FORMULA (R2SIO)X IN WHICH EACH R IS A GROUP FROM THE CLASS CONSISTING OF ALKYL GROUPS CONTAINING 1 TO 4 CARBON ATOMS, PHENYL, TOLYL AND ALPHA AND BETA NAPHTHYL, AND X IS 1400 TO 10,000, WHICH METHOD COMPRISES JOINING THE LINEAR HIGH MOLECULAR WEIGHT POLYSILOXANE AND A BUTADIENYL DILITHIUM IN AN ALKANE SOLVENT AND THEREBY PRODUCING SAID LINEAR ALTERNATING BLOCK COPOLYMER.
Claim 2
Independent Claim
109 words
THE METHOD OF PRODUCING A LINEAR ALTERNATING BLOCK COPOLYMER COMPOSED OF (A) 1 TO 80 PER CENT BY WEIGHT OF A POLYBUTADIENE WITH A VINYL CONTENT OF AT LEAST 60 PER CNE WEIGHT AND (B) 20 TO 99 PER CENT BY WEIGHT OF A LINEAR POLYSILOXANE HAVING THE FORMULA (R2SIO)X IN WHICH EACH R IS A GROUP FROM THE CLASS CONSISTING OF ALKYL GROUPS CONTAINING 1 TO 4 CARBON ATOMS, PHENYL, TOLYL AND ALPHA AND BETA NAPHTHYL, AND X IS 1400 TO 10,000, WHICH METHOD COMPRISES JOINING THE LINEAR HIGH MOLECULAR WEIGHT POLYSILOXANE AND A BUTADIENYL DILITHIUM IN AN ALKANE SOLVENT AND THEREBY PRODUCING SAID LINEAR ALTERNATING BLOCK COPOLYMER.
Claim 3
Dependent Claim
17 words
The process of claim 1 in which the polysiloxane is added to a solution of polybutadienyl dilithium.
Claim 4
Dependent Claim
17 words
The process of claim 1 in which polybutadienyl dilithium is added to a solution of the polysiloxane.
Claim 5
Dependent Claim
11 words
The process of claim 1 in which the polysiloxane is polydimethylsiloxane.
Claim 6
Dependent Claim
28 words
The process of claim 1 wherein said linear alternating block copolymer formed is further treated by neutralization with mineral acid to give a product of higher molecular weight.
References Cited (Backward Citations)
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US3244664A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-22 | 1979-06-23 | 1979-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-22 | 1983-06-23 | 1983-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-22 | 1987-06-23 | 1987-12-23 | $7700.00 | Window Closed / Lapsed |