A method for preparing lactic acid-containing waste from the polylactic acid segment of the ester

The present application belongs to the field of organic synthesis, particularly to a method for polylactic acid segment containing waste prepared lactate. The method provided herein includes the steps of: a), waste and alcohol over a catalyst to give a reaction solution; B), after the reaction was subjected to give lactate; polylactic acid in the waste content of the segment is 10 ~ 99wt%; degree of polymerization of the polylactic acid segment waste is 5 to 2000. The present application is based on polylactic acid segment containing waste as a starting material, is reacted with alcohols occur, lactate was prepared. In the present application, the manufacturing process does not require the use of lactic acid ester with a liquid, avoiding an increase in the use of a water carrier caused by environmental pollution and production costs. Simultaneous provided herein containing waste to be recycled to the polylactic acid segment has a certain economic and social benefits.