METHOD FOR PRODUCING POLYLACTIC ACID MICROPARTICLES, POLYLACTIC ACID MICROPARTICLES, AND CRYSTAL NUCLEATION AGENT, MOLDED ARTICLE, AND SURFACE MODIFIER USING THE SAME

摘要

Provided is a method for producing polylactic acid microparticles, which comprises: a preliminary step in which a polymer compound solution, which is obtained by dissolving in a first solvent a polymer compound containing structural units derived from l-lactic acid and structural units derived from d-lactic acid, is retained in a first liquid retaining part while a second solvent, which is a poor solvent of the polymer compound, is retained in a second liquid retaining part of a permeation device having two liquid retaining parts separated by a permeation membrane having pores with a diameter of 0.5 nm to 1,000 nm; and a permeation step in which the polymer compound solution retained in the first liquid retaining part is brought into contact with the second solvent by causing the polymer compound solution to permeate through the permeation membrane at a flow rate of 1×10^-3 mL/(min·cm²) to 10,000 mL/(min·cm²).