Patent US2745170A successfully refreshed from Google Patents.
Patent US3609181A successfully refreshed from Google Patents.
US3609181A
Expired / Lapsed
US
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Polyesters of polyoxytetramethylene glycol and certain dioic acids
Assignee: United States Department of the Air Force
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Filing: 1964-05-28
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Granted: 1971-09-28
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Expires: 1984-05-28
Abstract
Abstract 1. The process of making polyesters comprising the steps of heating a polyoxytetramethylene glycol having 10 to 15 oxytetramethylene groups with a dioic acid selected from the group consisting of sebacic, isosebacic, and azelaic acids, the anhydrides of said acids, and mixtures thereof at a temperature of 300* to 550* F. 6. The product formed by the process of claim 1.
Inventors
- 👤 Hyman R Lubowitz
- 👤 Charles J Rogers
- 👤 Raymond A Lynch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:12
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/66; C08G63/668; C06; C06B; C06B45/00; C06B45/04; C06B45/06; C06B45/10; C07; C07C; C07C67/00; C07C67/08; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/42; C08G18/4244; C08G18/4247; C08G18/4252
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
49 words
THE PROCESS OF MAKING POLYESTERS COMPRISING THE STEPS OF HEATING A POLYOXTETRAMETHYLENE GLYCOL HAVING 10 TO 15 OXYTETRAMETHYLENE GROUPS WITH A DIOIC ACID SELECTED FROM THE GROUP CONSISTING OF SEBACIC, ISOSEBACIC, AND AZELAIC ACIDS, THE ANHYDRIDES OF SAID ACIDS, AND MIXTURES THEROF AT A TEMPERATURE OF 300* TO 550*F.
Claim 2
Dependent Claim
49 words
THE PROCESS OF MAKING POLYESTERS COMPRISING THE STEPS OF HEATING A POLYOXTETRAMETHYLENE GLYCOL HAVING 10 TO 15 OXYTETRAMETHYLENE GROUPS WITH A DIOIC ACID SELECTED FROM THE GROUP CONSISTING OF SEBACIC, ISOSEBACIC, AND AZELAIC ACIDS, THE ANHYDRIDES OF SAID ACIDS, AND MIXTURES THEROF AT A TEMPERATURE OF 300* TO 550*F.
Claim 3
Dependent Claim
50 words
The process of making polyesters comprising the steps of heating a polyoxytetramethylene glycol having 10 to 15 oxytetramethylene groups with a dioic acid selected from the group consisting of sebacic, isosebacic, and azelaic acids, the anhydrides of said acids, and mixtures thereof at a temperature of 300* to 550* F.
Claim 4
Dependent Claim
50 words
The process of making polyesters comprising the steps of heating a polyoxytetramethylene glycol having 10 to 15 oxytetramethylene groups with a dioic acid selected from the group consisting of sebacic, isosebacic, and azelaic acids, the anhydrides of said acids, and mixtures thereof at a temperature of 300* to 550* F.
Claim 5
Dependent Claim
26 words
The process of claim 1 wherein the reaction takes place in the presence of a catalyst constituting 0.1 to 5 percent by weight of the reactants.
Claim 6
Dependent Claim
15 words
The process of claim 2 wherein the reaction takes place in an inert gas atmosphere.
Claim 7
Dependent Claim
19 words
The process of claim 3 wherein the reaction takes place in a temperature range from 350* to 420* F.
Claim 8
Dependent Claim
11 words
The process of claim 4 wherein the acid is sebacic acid.
Claim 9
Dependent Claim
9 words
The product formed by the process of claim 1.
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) | 1974-09-27 | 1975-03-29 | 1975-09-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-27 | 1979-03-29 | 1979-09-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-27 | 1983-03-29 | 1983-09-28 | $7700.00 | Window Closed / Lapsed |