Patent · US Expired

Continuous process for manufacture of lactide polymers with purification by distillation

US5357035A · kind A · utility

68Cited by
63References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 16, 1993
Grant dateOct 18, 1994
Priority date
Expiry dateSep 16, 2013

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08G63/06
  • 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.