EP0266603A1
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Preparation of anhydride copolymers
Assignee: Massachusetts Institute of Technology
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Filing: 1987-10-16
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Granted: —
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Expires: 2007-10-16
Abstract
Abstract A method for preparation of very pure anhydride copolymers with high yield. The anhydride copolymers, consisting of aromatic and aliphatic diacids are formed by melt condensation of individually prepared, pure, isolated prepolymers. The method of preparation is characterized by high yield, reproducibility, polymer purity and controlled composition, and is a short and convenient procedure. The polyanhydrides produced by the disclosed method are particularly well suited to biomedical applications requiring low levels of toxic or inflammatory contaminants and physical and mechanical properties which closely conform to manufacturing specifications.
Inventors
- 👤 Abraham J. Patent Att. Keil & Schaafhausen Domb
- 👤 Robert S. Patent Att. Keil & Schaafhausen Langer
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 01:50
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/20; A61K9/2004; A61K9/2022; A61K9/2031; C; C08; C08G; C08G67/00; C08G67/04
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
66 words
A method for preparing highly pure anhydride copolymers comprising: " selecting at least two diacids, wherein said diacids are synthesized and purified individually, reacting the individual diacids and acetic anhydride separately to form prepolymers. separately recrystallizing the individual prepolymers formed by the reaction of the acetic anhydride with said diacids, combining said individual prepolymers at a specific ratio, and polymerizing said prepolymer mixture to form copolymers.
Claim 2
Independent Claim
66 words
A method for preparing highly pure anhydride copolymers comprising: " selecting at least two diacids, wherein said diacids are synthesized and purified individually, reacting the individual diacids and acetic anhydride separately to form prepolymers. separately recrystallizing the individual prepolymers formed by the reaction of the acetic anhydride with said diacids, combining said individual prepolymers at a specific ratio, and polymerizing said prepolymer mixture to form copolymers.
Claim 3
Dependent Claim
30 words
The method of claim 1 wherein the diacids are selected from the group consisting of sebacic acid, bis(p-carboxyphenoxy)propane, bis(p-carboxyphenoxy)hexane, isophthalic acid, 1,4 phenylene dipropionic acid, adipic acid and dodecanedioic acid.
Claim 4
Dependent Claim
40 words
A highly pure anhydride copolymer comprising monomers selected from the group consisting of aliphatic and aromatic diacids, wherein the copolymers are polymerized from a mixture of a specific ratio of prepolymers of the individual monomers separately reacted with acetic anhydride.
Claim 5
Dependent Claim
40 words
A highly pure anhydride copolymer comprising monomers selected from the group consisting of aliphatic and aromatic diacids, wherein the copolymers are polymerized from a mixture of a specific ratio of prepolymers of the individual monomers separately reacted with acetic anhydride.
Claim 6
Dependent Claim
32 words
The anhydride copolymer of claim 3 wherein said prepolymers are formed by separately refluxing individual monomers with acetic anhydride to form individual prepolymers, removing the excess acetic anhydride, and recrystallizing the prepolymers.
Claim 7
Dependent Claim
14 words
The anhydride copolymer of claim 3 wherein the copolymers are further purified by recrystallization.
Claim 8
Dependent Claim
20 words
The anhydride copolymer of claim 3 wherein said copolymers are polymerized from said prepolymers in the presence of a catalyst.
References Cited (Backward Citations)
US3766145A
Cited
EP0180839A1
Cited
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