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US4248995A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the production of alkylaromatic copolyesters

Assignee: Rhone Poulenc Industries SA
•
Filing: 1979-09-25
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Granted: 1981-02-03
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Expires: 1999-09-25
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Abstract

Abstract A process is disclosed for the production of alkylaromatic copolyesters, characterized in that there are reacted, successively, at a temperature below 250° C., a diester of a dihydroxyaromatic compound and an aliphatid diacid of the general formula HOOC(CH 2 ) n COOH, in which 3≦n≦10, with a molar ratio of the diester to the diacid of between 1.5 and 4, until the degree of completion of the reaction is greater than or equal to 85%, and them, at a temperature above 250° C., an aromatic and/or cycloaliphatic dicarboxylic acid, and in that the product obtained is subjected to a polycondensation reaction under reduced pressure for a duration which is less than or equal to 1 hour 30 minutes. This process makes it possible to produce copolyesters which may be readily converted in the molten state to threads, films and molded articles.

Inventors

  • 👤 Bernard Fayolle

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 11:20
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/12; C08G63/16; C08G63/18; C08G63/19; C08G63/78

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 117 words
A process for the production of an alkylaromatic copolyester, characterized in that there are reacted, successively, at a temperature below 250° C., a diester of a dihydroxyaromatic compound and an aliphatic diacid of the general formula HOOC(CH 2 ) n COOH, in which 3≦n≦10, with a molar ratio of the diester to the diacid of between 1.5 and 4, until the degree of completion of the reaction is greater than or equal to 85%, and then, at a temperature above 250° C., an aromatic and/or cycloaliphatic dicarboxylic acid, and in that the product obtained is subjected to a polycondensation reaction under reduced pressure for a duration which is less than or equal to 1 hour 30 minutes.
Claim 2
Dependent Claim 117 words
A process for the production of an alkylaromatic copolyester, characterized in that there are reacted, successively, at a temperature below 250° C., a diester of a dihydroxyaromatic compound and an aliphatic diacid of the general formula HOOC(CH 2 ) n COOH, in which 3≦n≦10, with a molar ratio of the diester to the diacid of between 1.5 and 4, until the degree of completion of the reaction is greater than or equal to 85%, and then, at a temperature above 250° C., an aromatic and/or cycloaliphatic dicarboxylic acid, and in that the product obtained is subjected to a polycondensation reaction under reduced pressure for a duration which is less than or equal to 1 hour 30 minutes.
Claim 3
Dependent Claim 34 words
A process for the production of an alkylaromatic copolyester, according to claim 1, characterized in that the ratio of the diester of a dihydroxyaromatic compound to the aliphatic diacid is between 2 and 4.
Claim 4
Dependent Claim 38 words
A process for the production of an alkylaromatic copolyester, according to claim 1, characterized in that the degree of completion of the reaction of the diester of a dihydroxyaromatic compound with the aliphatic diacid is at least 90%.
Claim 5
Dependent Claim 40 words
A process for the production of an alkylaromatic copolyester, according to claim 1, characterized in that the temperature of the reaction of the diester of a dihydroxyaromatic compound with the aliphatic diacid is less than or equal to 240° C.
Claim 6
Dependent Claim 36 words
A process for the production of an alkylaromatic copolyester, according to claim 1, characterized in that the reaction of the diester of a dihydroxyaromatic compound with the aliphatic diacid is carried out under an inert atmosphere.
Claim 7
Dependent Claim 34 words
A process for the production of an alkylaromatic copolyester, according to claim 1, characterized in that the reaction of the diester of a dihydroxyaromatic compound with the aliphatic diacid is terminated under reduced pressure.
Claim 8
Dependent Claim 33 words
A process for the production of an alkylaromatic copolyester, according to claim 1, characterized in that the molar ratio of diester of a dihydroxyaromatic compound/total amount of diacids is between 0.95 and 1.05.
Claim 9
Dependent Claim 90 words
A process for the production of an alkylaromatic copolyester, according to claim 1, characterized in that the diester of dihydroxyaromatic compound is chosen from amongst compounds of the formula R--COO--X--OOCR, in which: R is a radical CH 3 (CH 2 ) n , in which n=0 to 8, and X is an ortho-, meta- or para-phenylene, 4,4'-diphenylene, diphenylene sulphone, diphenylene ether, diphenylenealkane or diphenoxyalkane radical, in which radicals each of the phenylene nuclei may contain 1 to 2 substituents chosen from amongst halogen atoms, and methyl, ethyl and methoxy radicals.
Claim 10
Dependent Claim 8 words
A process according to claim 9, wherein n=0.
Claim 11
Dependent Claim 95 words
A process for the production of an alkylaromatic copolyester, according to claim 1, characterized in that the aromatic or cycloaliphatic dicarboxylic acid is chosen from amongst the diacids of the formula HOOC-Y-COOH, in which Y represents a meta or para-phenylene, 1,3- or 1,4-cyclohexylene, 4,4'-diphenylene, diphenylene sulphone, diphenylene ether, diphenylenealkane or diphenoxyalkane radical, or a radical containing fused aromatic nuclei of which the free bonds are in the 2,6- or 2,7-positions, it being possible for each of the rings to contain 1 to 2 substituents chosen from amongst halogen atoms, and methyl, ethyl and methoxy radicals.
Claim 12
Dependent Claim 14 words
A process according to claim 10, wherein the halogen atoms are chlorine or bromine.

References Cited (Backward Citations)

US3567687A Cited
US3740375A Cited
US4064108A Cited
US4083829A Cited
US4071499A Cited
US4197393A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-02-03 1984-08-04 1985-02-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-02-03 1988-08-04 1989-02-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-02-03 1992-08-04 1993-02-03 $7700.00 Window Closed / Lapsed

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