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US3755283A
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Novel polymers and method of preparing same
Assignee: National Aeronautics and Space Administration
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Filing: 1971-05-19
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Granted: 1973-08-28
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Expires: 1991-05-19
Abstract
Abstract Polymers are prepared with terminal functional groups by reacting a compound selected from the group consisting of lithium p-lithiophenoxide and tetrabutylammonium p-lithiophenoxide as an initiator with material such as butadiene. The resulting functionally terminated new polymers are then capable of reacting with coupling agents to form star polymers.
Inventors
- 👤 J Fletcher
- 👤 S Hirshfield
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:46
CPC Classifications
C; C08; C08F; C08F36/00; C08F36/02; C08F36/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
18 words
The method of claim 1 wherein the polymerization is carried out at a temperature of at least 15*C.
Claim 2
Dependent Claim
18 words
The method of claim 1 wherein the polymerization is carried out at a temperature of 15* to 60*C.
Claim 3
Dependent Claim
20 words
The method of claim 1 wherein the amount of initiator is sufficient to provide a polymer with an LiO-terminal grouping.
Claim 4
Dependent Claim
11 words
The method of claim 1 wherein said monomeric material is butadiene.
Claim 5
Dependent Claim
40 words
The method according to claim 5 in which the solvent comprises tetrahydrofuran and the monomeric material is added to the initiator solution within 15 minutes of said reaction and the reaction is conducted at a temperature between 0*C and 30*C.
References Cited (Backward Citations)
US3326881A
Cited
US3631009A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-27 | 1977-02-26 | 1977-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-27 | 1981-02-26 | 1981-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-27 | 1985-02-26 | 1985-08-28 | $7700.00 | Window Closed / Lapsed |