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US4600753A
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US
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Two stage process for the production of aromatic polyester-carbonate
Assignee: Bayer AG
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Filing: 1984-12-10
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Granted: 1986-07-15
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Expires: 2004-12-10
Abstract
Abstract The invention relates to a process for the preparation of aromatic polyester-carbonates wherein, in a first stage, aromatic oligo-esters or oligo-ester-carbonates having hydroxyl end groups are prepared from diaryl esters of aromatic dicarboxylic acids (or their starting materials) and diphenols and, optionally, a diaryl carbonate, by trans-esterification in the melt, and in a second stage these oligo-esters or oligo-ester-carbonates are condensed with phosgene by the phase boundary process to give the polyester-carbonate.
Inventors
- 👤 Dieter Freitag
- 👤 Claus H. Wulff
- 👤 Gerhard Henes
- 👤 Ludwig Bottenbruch
- 👤 Peter Tacke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:45
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/64
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
111 words
A process for the production of an aromatic polyester-carbonate in which, in a first stage a diaryl ester of at least one aromatic dicarboxylic acid, or a mixture of at least one aromatic dicarboxylic acid and diphenyl carbonate, is reacted with 1.01 to 100 moles of at least one diphenol, per mole of diaryl ester, in the melt until an oligomer having a number-average molecular weight of 650 to 25,000 has been produced and thereafter, in a second stage, the oligomer is condensed with phosgene, using the phase boundary process, in the presence of a tertiary amine, a quaternary ammonium salt or a mixture of both to give the aromatic polyester-carbonate.
Claim 2
Dependent Claim
111 words
A process for the production of an aromatic polyester-carbonate in which, in a first stage a diaryl ester of at least one aromatic dicarboxylic acid, or a mixture of at least one aromatic dicarboxylic acid and diphenyl carbonate, is reacted with 1.01 to 100 moles of at least one diphenol, per mole of diaryl ester, in the melt until an oligomer having a number-average molecular weight of 650 to 25,000 has been produced and thereafter, in a second stage, the oligomer is condensed with phosgene, using the phase boundary process, in the presence of a tertiary amine, a quaternary ammonium salt or a mixture of both to give the aromatic polyester-carbonate.
Claim 3
Dependent Claim
27 words
A process according to claim 1, in which the first stage is carried out in the presence of a catalyst, a chain terminator or a branching agent.
Claim 4
Dependent Claim
27 words
A process according to claim 1 or 2, in which the first stage is carried out in the presence of diphenyl ether or ditolyl ether as solvent.
Claim 5
Dependent Claim
45 words
A process according to claim 1 or 2, in which the second stage is carried out using only such an amount of alkali metal hydroxide required to keep the pH value during phosgenation at 10 to 12, and adding the catalyst only after the phosgenation.
Claim 6
Dependent Claim
27 words
A process according to claim 1 or 2, in which the second stage is carried out in the presence of a chain terminator or a branching agent.
Claim 7
Dependent Claim
45 words
A process according to claim 1 or 2 in which the diphenol is reacted with a mixture of aromatic dicarboxylic acid and diaryl carbonate wherein more than 2 moles of diaryl carbonate per mole of aromatic dicarboxylic acid are present in the first stage reaction.
Claim 8
Dependent Claim
20 words
A process according to claim 1 or 2 wherein the first stage contains an additional diaryl carbonate as a reactant.
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) | 1989-07-14 | 1990-01-13 | 1990-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-14 | 1994-01-13 | 1994-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-14 | 1998-01-13 | 1998-07-15 | $7700.00 | Window Closed / Lapsed |