Process for preparing polylactic acid
AssigneeShimadzu Corporation
InventorsMasaaki Oota, Masahiro Ito
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Abstract
The polymerization reaction is conducted by heating a lactide, a cyclic imide compound (e.g. succinimide, etc.) and a polymerization catalyst (e.g. tin octylate, etc.) at 100-190.degree. C. with stirring under a nitrogen gas flow. It is preferred that an amount of the cyclic imide compound is from 1 to 35% by mole based on the lactide. Even if an amount of the polymerization catalyst is small, e.g. 0.00001-0.1 mole %, based on the lactide, polylactic acid can be efficiently prepared. It is possible to avoid remains of the catalyst in the polymer and coloring of the polymer.
Claims7
A process for preparing polylactic acid by ring-opening polymerization of a lactide in the presence of a polymerization catalyst, said process comprising adding a cyclic imide to a polymerization reaction system.
Dependencies are inferred from the claim text.