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Process for the preparation of aromatic polyesters

Assignee: Isovolta AG
•
Filing: 1983-02-03
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Granted: 1984-02-07
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Expires: 2003-02-03
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Abstract

Abstract In an improved process for the preparation of aromatic polyesters by polycondensation of diphenols with aromatic dicarboxylic acid halides such as isophthalic acid chloride and/or terephthalic acid chloride, by a two-phase interface polycondensation method wherein a fine dispersion is produced from an aqueous phase consisting of a solution of diphenol, alkali metal hydroxide for the formation of the alkali metal diphenolate in a stoichiometric ratio or in a slight excess and a phase transfer catalyst like triethylbenzylammonium chloride, tetrabutyl ammonium iodide or crown ether in a mixture of water and an organic solvent as a solubilizer with the organic liquid phase consisting of a solution of the acid chloride in a halogenated solvent, where the diphenolate, transferred to the liquid phase by the phase transfer catalyst, reacts with the acid chloride in a polycondensation reaction for the formation of the polyester, and the polyester formed remains dissolved in the organic phase the improvement comprising using as the solubilizer an alkanol of 2 to 5 carbon atoms or an alkoxy alkanol of 2 to 5 carbon atoms and polyester esters produced thereby.

Inventors

  • 👤 Werner Rieder

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 19:08
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/12; C08G63/16; C08G63/18; C08G63/19; C08G63/78; C08G63/79

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 107 words
In a process for the preparation of aromatic polyesters by a two phase, interfacial polycondensation wherein a fine dispersion is produced from an aqueous phase consisting of a diphenol, approximately an stoichiometric amount of an alkali metal hydroxide and a phase transfer catalyst in a mixture of water and an organic solubilizer and an organic phase of a solution of at least one aromatic dicarboxylic acid halide in a halogenated organic solvent with the polyester being dissolved in the organic phase, the improvement comprising using as the organic solubilizer an alkanol of 2 to 5 carbon atoms or an alkoxy alkanol of 2 to 5 carbon atoms.
Claim 2
Dependent Claim 107 words
In a process for the preparation of aromatic polyesters by a two phase, interfacial polycondensation wherein a fine dispersion is produced from an aqueous phase consisting of a diphenol, approximately an stoichiometric amount of an alkali metal hydroxide and a phase transfer catalyst in a mixture of water and an organic solubilizer and an organic phase of a solution of at least one aromatic dicarboxylic acid halide in a halogenated organic solvent with the polyester being dissolved in the organic phase, the improvement comprising using as the organic solubilizer an alkanol of 2 to 5 carbon atoms or an alkoxy alkanol of 2 to 5 carbon atoms.
Claim 3
Dependent Claim 17 words
The process of claim 1 wherein the solubilizer is an alkanol of 2 to 5 carbon atoms.
Claim 4
Dependent Claim 10 words
The process of claim 1 wherein the solubilizer is isopropanol.
Claim 5
Dependent Claim 10 words
The process of claim 1 wherein the solubilizer is ethanol.

References Cited (Backward Citations)

US3216970A Cited
US3234167A Cited
US4066623A Cited
US4201855A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-02-06 1987-08-08 1988-02-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-02-06 1991-08-08 1992-02-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-02-06 1995-08-08 1996-02-07 $7700.00 Window Closed / Lapsed

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