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US4055544A
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Process for making polycarbonates using ammonia or ammonia compounds as the catalysts
Assignee: Dow Chemical Co
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Filing: 1976-07-12
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Granted: 1977-10-25
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Expires: 1996-07-12
Abstract
Abstract Thermoplastic polycarbonates are prepared by interfacial polymerization wherein carbonyl halides, dihydric phenols and a catalytic amount of ammonia or an ammonium compound which liberates ammonia during the reaction are reacted. The polycarbonates thus prepared have chloroformate end groups and are useful as intermediates to be capped with various terminal groups in a know manner.
Inventors
- 👤 Joseph McClendon Baggett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:11
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/20; C08G64/22; C08G64/24
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
47 words
A process for making thermoplastic aromatic polycarbonates which comprises reacting under interfacial polycarbonate-forming conditions 1. a carbonyl halide, 2. a dihydric phenol or mixtures of dihydric phenols, and 3. a catalytic amount of ammonia or an ammonium compound which liberates ammonia under the conditions of the reaction.
Claim 2
Dependent Claim
47 words
A process for making thermoplastic aromatic polycarbonates which comprises reacting under interfacial polycarbonate-forming conditions 1. a carbonyl halide, 2. a dihydric phenol or mixtures of dihydric phenols, and 3. a catalytic amount of ammonia or an ammonium compound which liberates ammonia under the conditions of the reaction.
Claim 3
Dependent Claim
26 words
The process as set forth in claim 1 wherein the catalytic amount used from about 0.5 to about 5.0 weight percent based on the dihydric phenol.
Claim 4
Dependent Claim
68 words
A process for making thermoplastic polycarbonates which comprises reacting under interfacial polycarbonate-forming conditions 1. a carbonyl halide, 2. a dihydric phenol or mixtures of dihydric phenols, and 3. a catalytic amount of a compound having one of the formulas A. nh 3 b. nh 4 z or C. (nh 4 ) 2 z 1 wherein Z is a monovalent inorganic anion and Z is a divalent inorganic anion.
Claim 5
Dependent Claim
68 words
A process for making thermoplastic polycarbonates which comprises reacting under interfacial polycarbonate-forming conditions 1. a carbonyl halide, 2. a dihydric phenol or mixtures of dihydric phenols, and 3. a catalytic amount of a compound having one of the formulas A. nh 3 b. nh 4 z or C. (nh 4 ) 2 z 1 wherein Z is a monovalent inorganic anion and Z is a divalent inorganic anion.
Claim 6
Dependent Claim
32 words
The process as set forth in claim 3 wherein the catalytic compound has the formula NH.sub.4 Z wherein Z is selected from the group consisting of the chloride, hydroxide or nitrate anions.
Claim 7
Dependent Claim
34 words
The process as set forth in claim 3 wherein the catalytic compound has the formula (NH.sub.4).sub.2 Z wherein Z is selected from the group consisting of the sulfite, carbonate, sulfate, or hydrogen phosphite anions.
Claim 8
Dependent Claim
27 words
The process as set forth in claim 3 wherein the catalytic amount used is from about 0.5 to about 5.0 weight percent based on the dihydric phenol.
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) | 1980-10-24 | 1981-04-25 | 1981-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-24 | 1985-04-25 | 1985-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-24 | 1989-04-25 | 1989-10-25 | $7700.00 | Window Closed / Lapsed |