Continuous process for manufacture of lactide polymers with controlled optical purity
US6277951A · kind A · utility
35Cited by
67References
35Claims
0Family size
Assignee
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Key dates
| Filing date | Jul 13, 1999 |
| Grant date | Aug 21, 2001 |
| Priority date | — |
| Expiry date | Jul 13, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/08
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for the continuous production of polylactide polymers from lactic acid which incorporates removal of water or a solvent carrier to concentrate the lactic acid feed followed by polymerization to a low-molecular-weight prepolymer. This prepolymer is fed to a reactor in which a catalyst is added to facilitate generation of lactide, the depolymerization product of polylactic acid. The lactide generated is continuously fed to a distillation system as a liquid or vapor wherein water and other impurities are removed. The resultant purified liquid lactide is fed directly to a polymerization process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.