.

Pharmaceutical Business Intelligence

  • Anticipate P&T budget requirements
  • Evaluate market entry opportunities
  • Find generic sources and suppliers
  • Predict branded drug patent expiration

► Plans and Pricing

Upgrade to enjoy subscriber-only features like email alerts and data export. See the Plans and Pricing

DrugPatentWatch Database Preview

Claims for Patent: 4,789,724

« Back to Dashboard

Claims for Patent: 4,789,724

Title: Preparation of anhydride copolymers
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.
Inventor(s): Domb; Abraham J. (Brookline, MA), Langer; Robert S. (Somerville, MA)
Assignee: Massachusetts Institute of Technology (Cambridge, MA)
Application Number:06/920,724
Patent Claims: 1. A method for preparing highly pure anhydride copolymers comprising:

providing at least two individually synthetized and purified diacids,

reacting the individual diacids and acetic anhydride separately to form mixed anhydrides of the invididual diacids,

separately removing the unreacted acetic anhydride and diacids from the individual mixed anhydrides formed by the reaction of the acetic anhydride with said diacids,

combining said individual mixed anhydrides, and

polymerizing said mixture of the purified mixed anhydrides of the individual diacids to form copolymers.

2. The method of claim 1 wherein the diacids are selected form the group consisting of sebacic acid, bis(p-carboxyphenoxy-propane, bis(p-carboxyphenoxy)hexane, isophthalic acid, 1,4 phenylene diporpionic acid, adipic acid and dodecanedioic acid.

3. A highly pure anhydride copolymer consisting essentially of individually synthetisized and purified monomers selected from the group consisting of mixed anhydrides of aliphatic and aromatic diacids, wherein said diacids were individually reacted with acetic anhydride and the unreacted diacid and acetic anhydride removed after the reaction.

4. The anhydride copolymer of claim 3 wherein said mixed anhydrides are formed by

separately refluxing individual diacids with acetic anhydride to form individual mixed anhydrides,

removing the excess acetic anhydride, and

recrystallizing the individual mixed anhydrides.

5. The anhydride copolymer of claim 3 wherein the copolymers are further purified by recrystallization.
« Back to Dashboard

For more information try a trial or see the database preview and plans and pricing

How are People Using DrugPatentWatch?

Drugs may be covered by multiple patents or regulatory protections. All trademarks and applicant names are the property of their respective owners or licensors. Although great care is taken in the proper and correct provision of this service, thinkBiotech LLC does not accept any responsibility for possible consequences of errors or omissions in the provided data. The data presented herein is for information purposes only. There is no warranty that the data contained herein is error free. thinkBiotech performs no independent verifification of facts as provided by public sources nor are attempts made to provide legal or investing advice. Any reliance on data provided herein is done solely at the discretion of the user. Users of this service are advised to seek professional advice and independent confirmation before considering acting on any of the provided information. thinkBiotech LLC reserves the right to amend, extend or withdraw any part or all of the offered service without notice.

`abc