Patent US4460752A successfully refreshed from Google Patents.
US4460752A
Expired / Lapsed
US
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Reacting polycarbonate resin with aryl chlorocarbonate to improve aging characteristics
Assignee: Bayer AG
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Filing: 1982-10-25
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Granted: 1984-07-17
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Expires: 2002-10-25
Abstract
Abstract A process for the preparation of polycarbonates from diphenols and/or chlorocarbonic acid esters thereof and phosgene by the two-phase boundary process wherein said polycarbonate is reacted with aryl chlorocarbonate is disclosed; the reaction products are noted for their improved ageing and hydrolysis characteristics which render them useful as thermoplastic molding compositions.
Inventors
- 👤 Dieter Neuray
- 👤 Dieter Margotte
- 👤 Erhard Tresper
- 👤 Gunter Jacobs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:44
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/42; C08G64/20; C08G64/22; C08G64/24; C08G64/26; C08G64/28
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
152 words
A process for the preparation of a polycarbonate resin having a weight average molecular weight of at least 10,000 as determined by gel chromatography comprising reacting: (A) (i) at least one member selected from the group consisting of diphenols of the formula (I) HO--Z--OH wherein Z is a divalent aromatic radical and chlorocarbonic acid esters of a diphenol, (ii) about 0.1 to 8 mol % of phenol or a substituted monophenol and (iii) phosgene, in an organic solvent and an aqueous alkaline phase to produce a polycarbonate resin, and reacting (B) the polycarbonate resin of said (A) in solution in the organic phase after the aqueous alkaline phase has been separated off and before any acidic wash with about 0.1 to 1 mol % of at least one aryl chlorocarbonate of the formula (II) ##STR3## wherein Ar denotes a monovalent aromatic radical, said percents being relative to the mols of said (i).
Claim 2
Dependent Claim
152 words
A process for the preparation of a polycarbonate resin having a weight average molecular weight of at least 10,000 as determined by gel chromatography comprising reacting: (A) (i) at least one member selected from the group consisting of diphenols of the formula (I) HO--Z--OH wherein Z is a divalent aromatic radical and chlorocarbonic acid esters of a diphenol, (ii) about 0.1 to 8 mol % of phenol or a substituted monophenol and (iii) phosgene, in an organic solvent and an aqueous alkaline phase to produce a polycarbonate resin, and reacting (B) the polycarbonate resin of said (A) in solution in the organic phase after the aqueous alkaline phase has been separated off and before any acidic wash with about 0.1 to 1 mol % of at least one aryl chlorocarbonate of the formula (II) ##STR3## wherein Ar denotes a monovalent aromatic radical, said percents being relative to the mols of said (i).
Claim 3
Dependent Claim
19 words
A process according to claim 1 wherein the mol % of said (II) is 0.15 to 0.5 mol %.
Claim 4
Dependent Claim
21 words
A process according to claim 1, in which Z denotes, a divalent aromatic radical which contains 6 to 30 carbon atoms.
Claim 5
Dependent Claim
18 words
A process according to claim 1 wherein the mol % of (ii) is 0.5 to 5 mol %.
Claim 6
Dependent Claim
27 words
A process according to claim 1, in which Ar denotes a phenyl radical or an alkylphenyl radical having 1 to 8 carbon atoms in the alkyl radical.
Claim 7
Dependent Claim
28 words
A process according to claim 1, in which the aryl chlorocarbonate is added to the polycarbonate in the form of a solution in methylene chloride, toluene or chlorobenzene.
Claim 8
Dependent Claim
23 words
A process according to claim 1, in which the diphenol of formula (I) is selected from 2,2-bis-(4-hydroxyphenyl)-propane, 2,2-bis-(3,5-dimethyl-4-hydroxyphenyl)-propane, 2,2-bis-(3,5-dichloro-4-hydroxyphenyl)-propane, 2,2-bis-(3,5-dibromo-4-hydroxyphenyl)-propane, 1,1-bis-(4-hydroxyphenyl)-cyclohexane or bis-(4-hydroxyphenyl)-sulphone.
Claim 9
Dependent Claim
27 words
A process according to claim 1, in which the aryl chlorocarbonate of formula (II) is selected from the chlorocarbonic acid esters of phenol, p-tert.-butylphenol, 2,6-dimethylphenol or 4-(1,1,3,3-tetramethylbutyl)-phenol.
References Cited (Backward Citations)
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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) | 1987-07-17 | 1988-01-16 | 1988-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-17 | 1992-01-16 | 1992-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-17 | 1996-01-16 | 1996-07-17 | $7700.00 | Window Closed / Lapsed |