US3856754A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Linear homopolyesters and copolyesters based on methylene-bis(hydroxyalkyldimethyl hydantoins)
Assignee: DuPont de Nemours Deutschland GmbH
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Filing: 1973-08-09
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Granted: 1974-12-24
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Expires: 1993-08-09
Abstract
Abstract New homopolyesters and copolyesters are obtained by esterifying 1,1''-methylene-bis-(3-(hydroxy-alkyl)-5,5-dimethylhydantoins) and optionally alkanediols with terephthalic acid and/or isophthalic acid or their polyester-forming derivatives in a known manner, and subsequently polycondensing. The new homopolyesters and copolyesters are distinguished, relative to the conventional polyalkylene phthalates, by having better mechanical properties, and are in particular suitable for use as ''''Engineering Plastic'''' materials.
Inventors
- 👤 J Habermeier
- 👤 L Buxbaum
- 👤 H Batzer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:46
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/68; C08G63/685; C08G63/6854; C08G63/6856; C08G63/78; C08G63/80
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
42 words
A LINEAR, THERMOPLASTIC HOMOPOLYMER OR COPOLYESTER HAVING A RELATIVE VISCOSITY OF 0.5 - 3.0 DL/G, MEASURED AT 30*C ON A 1% STRENGTH SOLUTION CONSISTING OF EQUAL PARTS OF PHENOL AND TETRACHLOROETHANE, SAID POLYESTER CONSISTING ESSENTIALLY OF THE STRUCTURAL ELEMENT OF THE FORMULA
Claim 2
Dependent Claim
42 words
A LINEAR, THERMOPLASTIC HOMOPOLYMER OR COPOLYESTER HAVING A RELATIVE VISCOSITY OF 0.5 - 3.0 DL/G, MEASURED AT 30*C ON A 1% STRENGTH SOLUTION CONSISTING OF EQUAL PARTS OF PHENOL AND TETRACHLOROETHANE, SAID POLYESTER CONSISTING ESSENTIALLY OF THE STRUCTURAL ELEMENT OF THE FORMULA
Claim 3
Dependent Claim
58 words
A copolymer according to claim 1, of relative viscosity 1.0 to 2.5 dl/g, wherein in the formula, R denotes a hydrogen atom or the methyl group and R'' denotes a hydrogen atom, x represents a number from 2 to 4 and the ratio of n to m corresponds to the quotient of n/n + m 0.05 to 1.0.
Claim 4
Dependent Claim
16 words
A homopolyester according to claim 1, consisting essentially of the recurring structural element of the formula
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) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |