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US4393191A Expired / Lapsed US ⏱️ 0.0 years remaining

Preparation of aromatic polyesters by direct self-condensation of aromatic hydroxy acids

Assignee: Celanese Corp
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Filing: 1982-03-08
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Granted: 1983-07-12
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Expires: 2002-03-08
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Abstract

Abstract Provided is a method for preparing melt-processable polyesters efficiently via the direct polymerization of aromatic hydroxy acids. By the direct polymerization method, hydroxy and acid moieties are reacted directly without the use of acetylated reactants, thereby avoiding the disadvantages inherent in the case of acetylated reactants. The direct polymerization is conducted in the presence of a catalyst comprising a metal selected from the group consisting of the Group IV and V metals.

Inventors

  • 👤 Anthony J. East

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 13:22
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/06; C08G63/065

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 75 words
A process for preparing a wholly aromatic polyester comprising reacting at least one hydroxynaphthoic acid employed in an amount ranging from about 10 to 90 mole percent and at least one hydroxybenzoic acid in an amount from about 10 to 90 mole percent in the presence of a catalytic amount of a metallic compound selected from the group consisting of a Group IV or V metal salt, oxide and organometallic derivative under polymerization reaction conditions.
Claim 2
Dependent Claim 75 words
A process for preparing a wholly aromatic polyester comprising reacting at least one hydroxynaphthoic acid employed in an amount ranging from about 10 to 90 mole percent and at least one hydroxybenzoic acid in an amount from about 10 to 90 mole percent in the presence of a catalytic amount of a metallic compound selected from the group consisting of a Group IV or V metal salt, oxide and organometallic derivative under polymerization reaction conditions.
Claim 3
Dependent Claim 28 words
The process defined in claim 1 wherein the reaction temperature is sufficient to maintain at least one of the reactants and the resulting polyester in a melt phase.
Claim 4
Dependent Claim 15 words
The process defined in claim 1 or 2 wherein the catalyst is dialkyl tin diacetate.
Claim 5
Dependent Claim 19 words
The process defined in claim 1 or 2 wherein 6-hydroxy-2-naphthoic acid is reacted with at least one hydroxybenzoic acid.
Claim 6
Dependent Claim 19 words
The process defined in claim 1 or 2 wherein p-hydroxybenzoic acid is reacted with at least one hydroxynaphthoic acid.
Claim 7
Dependent Claim 16 words
The process defined in claim 1 or 2 wherein 6-hydroxy-2-naphthoic acid is reacted with p-hydroxybenzoic acid.
Claim 8
Dependent Claim 32 words
The process defined in claim 1 wherein the amount of catalyst employed is in the range of from about 0.001 to about 1 weight percent based upon the total monomer reactant weight.
Claim 9
Dependent Claim 24 words
The process defined in claim 7 wherein the amount of catalyst employed is in the range from about 0.05 to about 0.5 weight percent.
Claim 10
Dependent Claim 23 words
The process as defined in claim 2 wherein the reaction temperature is in the range from about 280° C. to about 360° C.
Claim 11
Dependent Claim 23 words
The process as defined in claim 9 wherein the reaction temperature is in the range from about 270° C. to about 320° C.
Claim 12
Dependent Claim 32 words
The process defined in claim 2 comprising reacting a composition consisting essentially of 6-hydroxy-2-naphthoic acid and p-hydroxybenzoic acid at a temperature in the range from about 280° C. to about 360° C.

References Cited (Backward Citations)

US4161470A Cited
US4256624A Cited
US4337190A Cited
US4318842A Cited
US4318841A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-07-11 1987-01-10 1987-07-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-07-11 1991-01-10 1991-07-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-07-11 1995-01-10 1995-07-12 $7700.00 Window Closed / Lapsed

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