Method for manufacturing poly(2-hydroxyalkanoic acid), and the poly(2-hydroxyalkanoic acid) obtainable thereby
US9663616B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Feb 11, 2014 |
| Grant date | May 30, 2017 |
| Priority date | — |
| Expiry date | Feb 11, 2034 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/912
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method for manufacturing poly(2-hydroxyalkanoic acid), preferably a poly(lactic acid), is disclosed. The method comprises the steps of: mixing a cyclic diester of a 2-hydroxyalkanoic acid and a polymerization catalyst, polymerizing the cyclic diester to form poly(2-hydroxyalkanoic acid) in liquid phase, adding a peroxide-based compound as a catalyst deactivating agent to the liquid phase, applying a devolatilization step to the liquid phase, and allowing the poly(2-hydroxyalkanoic acid) to solidify, characterized in that an end-capping agent is added to the poly(2-hydroxyalkanoic acid) in the liquid phase. The present invention also relates to a poly(2-hydroxyalkanoic acid), preferably a poly(lactic acid), obtainable with said method characterized in that the polymer has a Mn abs ranging between 10000 and 250000 g/mol, preferably between 20000 and 85000 g/mol.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.