US4071499A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High temperature polyester resins from 4,4'-bis(p-hydroxyphenoxy)diphenyl ether and terephthalic acid
Assignee: Celanese Corp
•
Filing: 1976-08-12
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Granted: 1978-01-31
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Expires: 1996-08-12
Abstract
Abstract This invention provides high temperature performance polyester resins which contain polyphenyl ether blocks as recurring structural units. The polyester resins are melt stable at temperatures up to about 400° C.
Inventors
- 👤 Robert W. Stackman
- 👤 Anthony B. Conciatori
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:54
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/66; C08G63/668; C08G63/672; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31786
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
13 words
A polyester resin composition which consists essentially of the recurring structural unit: ##STR4##
Claim 2
Dependent Claim
13 words
A polyester resin composition which consists essentially of the recurring structural unit: ##STR4##
Claim 3
Dependent Claim
30 words
A polyester resin in accordance with claim 1 which consists essentially of the condensation residues of 4,4'-bis(p-hydroxyphenoxy)diphenyl ether and terephthalic acid, and has a melting range below about 350° C.
Claim 4
Dependent Claim
23 words
A polyester resin in accordance with claim 2 which exhibits melt stability at temperatures in the range between about 350° and 400° C.
Claim 5
Dependent Claim
15 words
A polyester resin in accordance with claim 2 in the form a shaped molded article.
Claim 6
Dependent Claim
14 words
A polyester resin in accordance with claim 2 in the form of a fiber.
Claim 7
Dependent Claim
14 words
A polyester resin in accordance with claim 2 in the form of a film.
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) | 1981-01-30 | 1981-08-01 | 1982-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-30 | 1985-08-01 | 1986-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-30 | 1989-08-01 | 1990-01-31 | $7700.00 | Window Closed / Lapsed |