US3607841A
Expired / Lapsed
US
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Production of poly-2,2-disubstituted-beta-propiolactones
Assignee: Kanegafuchi Spinning Co Ltd
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Filing: 1968-03-06
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Granted: 1971-09-21
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Expires: 1988-03-06
Abstract
Abstract A method of producing poly- Alpha , Alpha -disubstituted- Beta propiolactones by ring-opening polymerizing a compound of the formula wherein R1 and R2 are aryl or alkyl having 1-4 carbon atoms, in the presence of an anionic polymerization catalyst, characterized by conducting the polymerization in the presence of a molecular weight controlling agent selected from the group consisting of acid anhydrides, aldehydes, sulfoxides, organic acids and phenolic compounds in order to control the molecular weight of the polymer.
Inventors
- 👤 Masataka Nakahara
- 👤 Yasuhiro Ogawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:22
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/06; C08G63/08
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
24 words
A method as claimed in claim 1 wherein the aldehydes are acetaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, caproaldehyde, enanthaldehyde, caprylaldehyde, pelargonaldehyde, caprinaldehyde, palmitaldehyde, stearaldehyde and benzaldehyde.
Claim 2
Dependent Claim
16 words
A method as claimed in claim 1 wherein the sulfoxides are dimethyl sulfoxide and diethyl sulfoxide.
Claim 3
Dependent Claim
33 words
A method as claimed in claim 1 wherein the anionic polymerization catalyst is selected from the group consisting of tri-n-butyl amine, triethyl amine, calcium acetate, n-butyl lithium, phenyl magnesium bromide and tributyl phosphine.
Claim 4
Dependent Claim
21 words
A method as claimed in claim 1 wherein the polymerization is conducted at a temperature of 0*-150* C., preferably 50*-120* C.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-20 | 1975-03-22 | 1975-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-20 | 1979-03-22 | 1979-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-20 | 1983-03-22 | 1983-09-21 | $7700.00 | Window Closed / Lapsed |