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US4889911A
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Process for the production of fully aromatic, thermotropic polyesters and polyester carbonates
Assignee: Bayer AG
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Filing: 1988-08-11
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Granted: 1989-12-26
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Expires: 2008-08-11
Abstract
Abstract Thermotropic, fully aromatic polyesters and polyester carbonates are produced by esterification of optionally substituted p-hydroxybenzoic acids and aromatic dicarboxylic acids with diaryl carbonate at temperatures in the range from 100° to 220° C. and subsequent transesterification of the aryl ester obtained with diphenols and, optinally, more diaryl carbonate, accompanied by polycondensation, at temperatures in the range from 250° to 330° C., the esterification, the transesterification and the polycondensation being carried out in the presence of heterocyclic compounds containing 1 to 3 nitrogen atoms.
Inventors
- 👤 Harald Pielartzik
- 👤 Wolfgang Ebert
- 👤 Rolf-Volker Meyer
- 👤 Hans-Joachim Traenckner
- 👤 Edgar Ostlinning
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 08:19
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/60; C08G63/605; C08G63/64; C08G63/78; C08G63/82; C08G63/87
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
101 words
A process for the production of thermotropic, fully aromatic polyesters and polyesters carbonates by (i) esterification of unsubstituted or substituted p-hydroxybenzoic acids and aromatic dicarboxylic acids with diaryl carbonate at temperatures of 100° to 220° C. and (ii) subsequent transesterification of the aryl esters from (i) with diphenols accompanied by polycondensation, at temperatures in the range from 250° to 330° C. wherein esterification, the transesterification and the polycondensation reactions are carried out in the presence of 0.01 to 5% by weight of at least one heterocyclic compound containing 1 to 3 nitrogen atoms, based on the amount of carboxylic acid reactant
Claim 2
Dependent Claim
101 words
A process for the production of thermotropic, fully aromatic polyesters and polyesters carbonates by (i) esterification of unsubstituted or substituted p-hydroxybenzoic acids and aromatic dicarboxylic acids with diaryl carbonate at temperatures of 100° to 220° C. and (ii) subsequent transesterification of the aryl esters from (i) with diphenols accompanied by polycondensation, at temperatures in the range from 250° to 330° C. wherein esterification, the transesterification and the polycondensation reactions are carried out in the presence of 0.01 to 5% by weight of at least one heterocyclic compound containing 1 to 3 nitrogen atoms, based on the amount of carboxylic acid reactant
Claim 3
Dependent Claim
27 words
A process as claimed in claim 1 wherein the esterification, transesterification and polycondensation reactions are carried out without isolation of the intermediate products in a one-pot process.
Claim 4
Dependent Claim
31 words
A process as claimed in claim 1 wherein the heterocyclic compound containing 1 to 3 nitrogen atoms is in a quantity of 0.1 2.5% by weight, based on the carboxylic acids.
Claim 5
Dependent Claim
43 words
A process as claimed in claim 1 wherein the heterocyclic compound is at least one member selected from the group consisting of imidazole, 4,5-diphenyl-1H-imidazole, 1,10-phenanthroline, 2,2'-bipyridyl, 1H-benzimidazole, 1,2-dimethyl-1H benzimidazole, 2-methyl-1H-imidazole, 1-methyl-1H-imidazole, 1H-pyrazole, 4-dimethyl aminopyridine, 4-pyrrolidinopyridine, 1,8-diazabicyclo-5, 4,0-undec-7-ene, 1,8-diazabicyclo-4,3,0-non-5-ene, 1,4-diazabi- cyclo-2,2,2-octane and 1,4,5,6-tetrahydro-1,2-dimethyl pyrimidine.
Claim 6
Dependent Claim
13 words
A process as claimed in claim 1 wherein imidazole is the heterocyclic compound.
Claim 7
Dependent Claim
36 words
A process as claimed in claim 1 wherein the p-hydroxybenzoic acid is ring-substituted by C 1 -C 4 alkyl, C 1 -C 4 alkoxy, C 6 -C 12 aryl, C 6 -C 10 alkylaryl or halogen.
Claim 8
Dependent Claim
33 words
A process as claimed in claim 6 wherein the p-hydroxybenzine acid is 4-hydroxy-2-methyl benzoic acid, 4-hydroxy-3-methyl benzoic acid, 2-ethyl-4-hydroxybenzoic acid, 3-ethyl-4-hydroxybenzoic acid, 2- or 3-chloro-4-hydroxybenzoic acid, 4-hydroxy-3-phenyl benzoic acid or 4-hydroxy-3-phenyl benzoic acid.
Claim 9
Dependent Claim
15 words
A process as claimed in claim 1 wherein the p-hydroxybenzoic acid is unsubstituted p-hydroxybenzoic acid.
Claim 10
Dependent Claim
21 words
A process as claimed in claim 1 wherein the transesterification (ii) of the aryl esters is with diphenols and diaryl carbonate.
References Cited (Backward Citations)
US4297455A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-12-25 | 1993-06-26 | 1993-12-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-12-25 | 1997-06-26 | 1997-12-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-12-25 | 2001-06-26 | 2001-12-26 | $7700.00 | Window Closed / Lapsed |