Continuous process for manufacture of a purified lactide
US5274073A · kind A · utility
82Cited by
56References
30Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 24, 1992 |
| Grant date | Dec 28, 1993 |
| Priority date | — |
| Expiry date | Aug 24, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G63/06
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for the continuous conversion of crude lactic acid to a substantially purified lactide or polylactide including the steps of polymerizing the lactic acid to form a prepolymer with subsequent depolymerization to form a crude lactide in the presence of a catalyst. The crude lactide is purified in an improved distillation system in which at least three fractions are formed with the substantially purified lactide removed as an intermediate boiling sidedraw stream. The substantially purified lactide may then be polymerized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.