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US4550155A
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Preparation of branched polycarbonates by transesterification with a triaryl tricarboxylic acid branching agent
Assignee: General Electric Co
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Filing: 1983-11-03
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Granted: 1985-10-29
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Expires: 2003-11-03
Abstract
Abstract This invention relates to branched polycarbonates that are made by transesterification having a triaryl tricarboxylic acid as a branching agent.
Inventors
- 👤 James F. Jones
- 👤 John B. Starr, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:32
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/04; C08G64/06; C08G64/14
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
69 words
A method of making a high molecular weight, thermoplastic randomly branched polycarbonate having an intrinsic viscosity of 0.30 to 1.0 which comprises polymerizing an aromatic dihydric phenol by transesterification with a diaryl carbonate in the presence of from about 0.01 to about 1.0 mole percent, based on the moles of the aromatic dihydric phenol, of a branching agent consisting solely of a triaryl ester of a trifunctional carboxylic acid.
Claim 2
Independent Claim
69 words
A method of making a high molecular weight, thermoplastic randomly branched polycarbonate having an intrinsic viscosity of 0.30 to 1.0 which comprises polymerizing an aromatic dihydric phenol by transesterification with a diaryl carbonate in the presence of from about 0.01 to about 1.0 mole percent, based on the moles of the aromatic dihydric phenol, of a branching agent consisting solely of a triaryl ester of a trifunctional carboxylic acid.
Claim 3
Dependent Claim
24 words
A method of making a high molecular weight, thermoplastic randomly branched polycarbonate as defined in claim 1 wherein said aromatic dihydric phenol is 2,2-bis(4-hydroxyphenyl)propane.
Claim 4
Dependent Claim
24 words
A method of making a high molecular weight, thermoplastic randomly branched polycarbonate as defined in claim 1 wherein the diaryl carbonate is diphenyl carbonate.
Claim 5
Dependent Claim
58 words
A method of making a high molecular weight, thermoplastic randomly branched polycarbonate as defined in claim 2, wherein the triaryl ester of a tri-carboxylic acid is of the formula: ##STR2## wherein R 1 , R 2 and R 3 are independently selected from the group consisting of hydrogen and lower alkyl of from 1 to 6 carbon atoms.
Claim 6
Dependent Claim
28 words
A method of making a high molecular weight, thermoplastic randomly branched polycarbonate as defined in claim 3 wherein the triaryl ester of a tri-carboxylic acid is triphenyl trimellitate.
Claim 7
Independent Claim
37 words
A method of making a high molecular weight, thermoplastic randomly branched polycarbonate which comprises transesterifying 2,2-bis(4-hydroxyphenyl)propane with diphenyl carbonate in the presence of 0.03 to 0.30 mole %, based on the moles of 2,2-bis(4-hydroxyphenyl)propane, of triphenyl trimellitate.
Claim 8
Independent Claim
37 words
A method of making a high molecular weight, thermoplastic randomly branched polycarbonate which comprises transesterifying 2,2-bis(4-hydroxyphenyl)propane with diphenyl carbonate in the presence of 0.03 to 0.30 mole %, based on the moles of 2,2-bis(4-hydroxyphenyl)propane, of triphenyl trimellitate.
Claim 9
Dependent Claim
47 words
A method of making a high molecular weight, thermoplastic randomly branched polycarbonate as defined in claim 1, wherein the amount of said triaryl ester of a trifunctional carboxylic acid is from about 0.03 to about 0.3 mole percent, based on the moles of the aromatic dihydric phenol.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-10-28 | 1989-04-29 | 1989-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-28 | 1993-04-29 | 1993-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-28 | 1997-04-29 | 1997-10-29 | $7700.00 | Window Closed / Lapsed |