US4105641A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of aliphatic polycarbonates and polyurethanes therefrom
Assignee: Bayer AG
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Filing: 1977-03-17
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Granted: 1978-08-08
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Expires: 1997-03-17
Abstract
Abstract The present invention relates to a process for the preparation of polycarbonates which contain aliphatically bound hydroxyl groups by transesterification of aliphatic dihydroxy compounds with glycol carbonate, optionally in the presence of transesterification catalysts, with simultaneous separation of the glycol by fractional distillation, which process is characterized in that ethylene glycol is removed from the reaction mixture as an azeotropic mixture by means of inert solvents with which ethylene glycol is substantially immiscible. The present invention further relates to the preparation of polyurethanes from these polycarbonates.
Inventors
- 👤 Hans-Josef Buysch
- 👤 Heinrich Krimm
- 👤 Hans Rudolph
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 02:04
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/02; C08G64/0208; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/42; C08G18/44; C08G64/16; C08G64/1608; C08G64/20; C08G64/30; C08G64/305
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
109 words
A transesterification process for the preparation of polycarbonates containing aliphatically bound hydroxyl end groups comprising: (a) reacting (i) aliphatic dihydroxyl compounds with (ii) glycol carbonate, in the presence of (iii) inert solvents selected from the group of compounds consisting of toluene, xylene, ethylbenzene, cumene, 1,2,4-trimethylbenzene, mesitylene, tetramethylbenzene, cymene, diethylbenzene, diisopropylbenzene, chlorotoluene, bromobenzene, tetralin, propenylbenzene, allylbenzene, α-methylstyrene, dibutylether, diisobutylether, diamylether, anisole, phenetole, cresol methyl ether, dibutyl ketone, di-tert.-butyl ketone and diamyl ketone, in which ethylene glycol is substantially immiscible, said inert solvents being capable of forming azeotropes with the ethylene glycol to permit selective azeotropic separation of said ethylene glycol; and (b) simultaneously separating the ethylene glycol by fractional distillation.
Claim 2
Dependent Claim
109 words
A transesterification process for the preparation of polycarbonates containing aliphatically bound hydroxyl end groups comprising: (a) reacting (i) aliphatic dihydroxyl compounds with (ii) glycol carbonate, in the presence of (iii) inert solvents selected from the group of compounds consisting of toluene, xylene, ethylbenzene, cumene, 1,2,4-trimethylbenzene, mesitylene, tetramethylbenzene, cymene, diethylbenzene, diisopropylbenzene, chlorotoluene, bromobenzene, tetralin, propenylbenzene, allylbenzene, α-methylstyrene, dibutylether, diisobutylether, diamylether, anisole, phenetole, cresol methyl ether, dibutyl ketone, di-tert.-butyl ketone and diamyl ketone, in which ethylene glycol is substantially immiscible, said inert solvents being capable of forming azeotropes with the ethylene glycol to permit selective azeotropic separation of said ethylene glycol; and (b) simultaneously separating the ethylene glycol by fractional distillation.
Claim 3
Dependent Claim
13 words
A process according to claim 1 conducted in the absence of transesterification catalysts.
Claim 4
Dependent Claim
13 words
A process according to claim 1 conducted in the presence of transesterification catalysts.
Claim 5
Dependent Claim
28 words
A process according to claim 3 wherein the transesterification catalysts are present in from about 0.0001 to 0.5% by weight based on the weight of the reaction mixture.
Claim 6
Dependent Claim
28 words
A process according to claim 1 wherein the substances used as inert solvents and formers of azeotropic mixtures are subsequently circulated over a substance which absorbs ethylene glycol.
Claim 7
Dependent Claim
28 words
In a process for the preparation of polyurethanes from hydroxyl-bearing compounds, the improvement comprising reacting the polycarbonates prepared according to the process of claim 1 with a polyisocyanate.
Claim 8
Dependent Claim
115 words
In a process for the preparation of polycarbonates containing aliphatically bound hydroxyl end groups comprising transesterification of aliphatic dihydroxyl compounds with glycol carbonate with simultaneous separation of ethylene glycol by fractional distillation, the improvement comprising removing ethylene glycol from the reaction mixture as an azeotropic mixture with inert solvents selected from the group of compounds consisting of toluene, xylene, ethylbenzene, cumene, 1,2,4-trimethylbenzene, mesitylene, tetramethylbenzene, cymene, diethylbenzene, diisopropylbenzene, chlorotoluene, bromobenzene, tetralin, propenylbenzene, allylbenzene, α-methylstyrene, dibutylether, diisobutylether, diamylether, anisole, phenetole, cresol methyl ether, dibutyl ketone, di-tert.-butyl ketone and diamyl ketone, in which ethylene glycol is substantially immiscible, said inert solvents being capable of forming azeotropes with ethylene glycol to permit selective azeotropic separation of said ethylene glycol.
Claim 9
Dependent Claim
115 words
In a process for the preparation of polycarbonates containing aliphatically bound hydroxyl end groups comprising transesterification of aliphatic dihydroxyl compounds with glycol carbonate with simultaneous separation of ethylene glycol by fractional distillation, the improvement comprising removing ethylene glycol from the reaction mixture as an azeotropic mixture with inert solvents selected from the group of compounds consisting of toluene, xylene, ethylbenzene, cumene, 1,2,4-trimethylbenzene, mesitylene, tetramethylbenzene, cymene, diethylbenzene, diisopropylbenzene, chlorotoluene, bromobenzene, tetralin, propenylbenzene, allylbenzene, α-methylstyrene, dibutylether, diisobutylether, diamylether, anisole, phenetole, cresol methyl ether, dibutyl ketone, di-tert.-butyl ketone and diamyl ketone, in which ethylene glycol is substantially immiscible, said inert solvents being capable of forming azeotropes with ethylene glycol to permit selective azeotropic separation of said ethylene glycol.
Claim 10
Dependent Claim
13 words
A process according to claim 7 conducted in the absence of transesterification catalysts.
Claim 11
Dependent Claim
13 words
A process according to claim 7 conducted in the presence of transesterification catalysts.
Claim 12
Dependent Claim
28 words
A process according to claim 9 wherein the transesterification catalysts are present in from about 0.0001 to 0.5% by weight based on the weight of the reaction mixture.
Claim 13
Dependent Claim
28 words
A process according to claim 7 wherein the substances used as inert solvents and formers of azeotropic mixtures are subsequently circulated over a substance which absorbs ethylene glycol.
Claim 14
Dependent Claim
28 words
In a process for the preparation of polyurethanes from hydroxyl-bearing compounds, the improvement comprising reacting the polycarbonates prepared according to the process of claim 7 with a polyisocyanate.
Claim 15
Dependent Claim
85 words
A transesterification process for the preparation of polycarbonates containing aliphatically bound hydroxyl end groups comprising: (a) reacting (i) aliphatic dihydroxyl compounds with (ii) glycol carbonate, in the presence of (iii) inert solvents selected from the group of ketones consisting of dibutyl ketone, di-tert.-butyl ketone and diamyl ketone in which ethylene glycol is substantially immiscible, said inert solvents being capable of forming azeotropes with the ethylene glycol to permit selective azeotropic separation of said ethylene glycol; and (b) simultaneously separating the ethylene glycol by fractional distillation.
Claim 16
Dependent Claim
85 words
A transesterification process for the preparation of polycarbonates containing aliphatically bound hydroxyl end groups comprising: (a) reacting (i) aliphatic dihydroxyl compounds with (ii) glycol carbonate, in the presence of (iii) inert solvents selected from the group of ketones consisting of dibutyl ketone, di-tert.-butyl ketone and diamyl ketone in which ethylene glycol is substantially immiscible, said inert solvents being capable of forming azeotropes with the ethylene glycol to permit selective azeotropic separation of said ethylene glycol; and (b) simultaneously separating the ethylene glycol by fractional distillation.
Claim 17
Dependent Claim
91 words
In a process for the preparation of polycarbonates containing aliphatically bound hydroxyl end groups comprising transesterification of aliphatic dihydroxyl compounds with glycol carbonate with simultaneous separation of ethylene glycol by fractional distillation, the improvement comprising removing ethylene glycol from the reaction mixture as an azeotropic mixture with inert solvents selected from the group of ketones consisting of dibutyl ketone, di-tert.-butyl ketone and diamyl ketone in which ethylene glycol is substantially immiscible, said inert solvents being capable of forming azeotropes with ethylene glycol to permit selective azeotropic separation of said ethylene glycol.
Claim 18
Dependent Claim
91 words
In a process for the preparation of polycarbonates containing aliphatically bound hydroxyl end groups comprising transesterification of aliphatic dihydroxyl compounds with glycol carbonate with simultaneous separation of ethylene glycol by fractional distillation, the improvement comprising removing ethylene glycol from the reaction mixture as an azeotropic mixture with inert solvents selected from the group of ketones consisting of dibutyl ketone, di-tert.-butyl ketone and diamyl ketone in which ethylene glycol is substantially immiscible, said inert solvents being capable of forming azeotropes with ethylene glycol to permit selective azeotropic separation of said ethylene glycol.
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) | 1981-08-07 | 1982-02-06 | 1982-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-08-07 | 1986-02-06 | 1986-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-08-07 | 1990-02-06 | 1990-08-08 | $7700.00 | Window Closed / Lapsed |