Patent US4235442A successfully refreshed from Google Patents.
EP0618249A2
Expired / Lapsed
EP
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Aliphatic polyester and preparation process thereof
Assignee: Mitsui Chemicals Inc
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Filing: 1994-03-30
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Granted: —
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Expires: 2014-03-30
Abstract
Abstract A preparation process of aliphatic polyester having a weight average molecular weight of 15,000 or more by conducting a direct polycondensation reaction of an aliphatic polyhydric alcohol or a mixed aliphatic polyhydric alcohol and an aliphatic polybasic acid or a mixed aliphatic polybasic acid, or additionally a hydroxycarboxylic acid or a mixed hydroxycarboxylic acid or an oligomer of the hydroxycarboxylic acid in a reaction mixture containing an organic solvent. The aliphatic polyester thus obtained contains an extremely small amount of impurities, has low color and can exhibit satisfactory strength in the form of films, filaments and other shaped articles.
Inventors
- 👤 Takeshi 543 Goshitsu Kashima
- 👤 Taiji 543 Goshitsu Kameoka
- 👤 Chojiro Higuchi
- 👤 Masanobu Ajioka
- 👤 Akihiro Yamaguchi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 17:18
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/60; C08G63/12; C08G63/16; C08G63/78; C08G63/81
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
73 words
A process for preparing an aliphatic polyester having a weight average molecular weight of 15,000 or more, which comprises subjecting a monomer composition, selected from (i) a mixture of one or more aliphatic polyhydric alcohol(s) and one or more aliphatic polybasic acid(s) and (ii) a mixture of one or more aliphatic polyhydric alcohol(s), one or more aliphatic polybasic acid(s) and one or more hydroxycarboxylic acid(s), to a polycondensation reaction in an organic solvent.
Claim 2
Dependent Claim
56 words
The process of claim 1 wherein a portion or more of the organic solvent containing water or the monomer(s) is removed from the reaction mixture and an additional organic solvent having a content of water and monomer which is same as or less than that of the removed organic solvent is charged to the reaction mixture.
Claim 3
Dependent Claim
57 words
The process of claim 2 wherein the organic solvent removed from the reaction mixture is brought into contact with a treatment agent selected from the group consisting of a drying agent, adsorbent and a mixture of these agents to remove water and the excess monomer(s), and is successively returned to the reaction mixture as the additional solvent.
Claim 4
Dependent Claim
19 words
The process of claim 3 wherein the drying agent is a molecular sieve, diphosphorus pentoxide or a metal hydride.
Claim 5
Dependent Claim
12 words
The process of claim 3 wherein the adsorbent is a molecular sieve.
Claim 6
Dependent Claim
24 words
The process of claim 3 wherein the additional organic solvent charged to the reaction mixture contains 50 ppm or less of water and monomer(s).
Claim 7
Dependent Claim
31 words
The process of claim 2 wherein water is initially removed from the reaction mixture by azeotropic distillation and successively a portion of the organic solvent is removed from the reaction mixture.
Claim 8
Dependent Claim
50 words
The process of any of the claims 1 to 7 wherein the organic solvent is selected from the group consisting of an ether solvent, a diphenyl ether solvent and a mixture of these solvents, or from the group consisting of anisole, phenethole, diphenyl ether and a mixture of these solvents.
Claim 9
Dependent Claim
23 words
The process of any of the claims 1 to 8, wherein the polyhydric alcohol is an aliphatic diol, preferably ethylene glycol or 1,4-butanediol.
Claim 10
Dependent Claim
25 words
The process of any of the claims 1 to 9, wherein the polybasic acid is an aliphatic dicarboxylic acid, preferably succinic acid or adipic acid.
Claim 11
Dependent Claim
21 words
The process of any of the claims 1 to 10, wherein the hydroxycarboxylic acid is an oligomer of a hydroxycarboxylic acid.
Claim 12
Dependent Claim
17 words
The process of any of the claims 1 to 10, wherein the hydroxycarboxylic acid is lactic acid.
Claim 13
Dependent Claim
23 words
The process of any of the claims 1 to 12, wherein the polycondensation reaction is carried out in the presence of a catalyst.
Claim 14
Dependent Claim
36 words
A process for the purification of aliphatic polyester comprising bringing a solid aliphatic polyester obtained by the preparation process of claim 13 into contact with an acidic substance in the presence of a hydrophilic organic solvent.
Claim 15
Dependent Claim
26 words
An aliphatic polyester obtained by the process of any of the claims 1 to 12 and having a weight average molecular weight of 15,000 or more.
Claim 16
Dependent Claim
22 words
An aliphatic polyester obtained by the preparation process of claim 6 and having a weight average molecular weight of 50,000 or more.
Claim 17
Dependent Claim
20 words
An aliphatic polyester obtained by the process of claim 14 and having a catalyst content of 50 ppm or less.
Claim 18
Dependent Claim
29 words
An aliphatic polyester obtained by the preaparation process of any of the claims 1 to 14 and having a Hazen number of 100 or less in the molten state.
References Cited (Backward Citations)
No citation records indexed.
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