US4379915A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lactone polymer
Assignee: Daicel Corp
•
Filing: 1982-02-23
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Granted: 1983-04-12
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Expires: 2002-02-23
Abstract
Abstract A lactone polymer has a narrow molecular weight distribution where a ratio of the weight average molecular weight to the number average molecular weight is in the range of from 1.1 to 2.0 and the molecular weight is 500 to 5,000.
Inventors
- 👤 Shoji Watanabe
- 👤 Takuya Miho
- 👤 Tatsumi Fujii
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 01:31
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/42; C08G18/4266; C08G18/4269; C08G18/4277; C08G63/00; C08G63/02; C08G63/06; C08G63/08; C08G63/78; C08G63/82; C08G63/823
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
79 words
A process for the preparation of lactone polymers, which comprises subjecting a lactone to ring-opening polymerization in the presence of 0.1 to 50 ppm of a stannous halide selected from the group consisting of stannous chloride, stannous bromide and stannous iodide, to form a lactone polymer in which the ratio of the weight average molecular weight to the number average molecular weight is in the range of from 1.1 to 2.0 and the molecular weight is 500 to 5,000.
Claim 2
Dependent Claim
79 words
A process for the preparation of lactone polymers, which comprises subjecting a lactone to ring-opening polymerization in the presence of 0.1 to 50 ppm of a stannous halide selected from the group consisting of stannous chloride, stannous bromide and stannous iodide, to form a lactone polymer in which the ratio of the weight average molecular weight to the number average molecular weight is in the range of from 1.1 to 2.0 and the molecular weight is 500 to 5,000.
Claim 3
Dependent Claim
12 words
A process claimed in claim 1 in which said lactone is epsilon-caprolactone.
References Cited (Backward Citations)
US2890208A
Cited
US3169945A
Cited
US3284417A
Cited
GB1201909A
Cited
US3663515A
Cited
US4300565A
Cited
US4289873A
Cited
US4357462A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-04-11 | 1986-10-11 | 1987-04-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-04-11 | 1990-10-11 | 1991-04-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-04-11 | 1994-10-11 | 1995-04-12 | $7700.00 | Window Closed / Lapsed |