Methods for converting linear polyesters to macrocyclic oligoester compositions and macrocyclic oligoesters
US6525164B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 31, 2001 |
| Grant date | Feb 25, 2003 |
| Priority date | — |
| Expiry date | Aug 31, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P20/582
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Macrocyclic oligoesters and compositions comprising macrocyclic oligoesters are prepared from intermediate molecular weight polyesters. In one embodiment, a diol is contacted with a dicarboxylic acid or a dicarboxylate in the presence of a catalyst to produce a composition comprising a hydroxyalkyl-tenninated polyester oligomer. The hydroxyalkyl-terminated polyester oligomer is heated to produce a composition comprising an intermediate molecular weight polyester which preferably has a molecular weight between about 20,000 Daltons and about 70,000 Daltons. The intermediate molecular weight polyester is heated and a solvent is added prior to or during the heating process to produce a composition comprising a macrocyclic oligoester. An optional step is to separate the macrocyclic oligoester from the composition comprising the macrocyclic oligoester.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.