Characterization of poly(<scp>D</scp>,<scp>L</scp>‐lactic acid) by gel permeation chromatography

Abstract

Abstract A number of samples of poly( D , L ‐lactic acid) (PLA) with weight‐average molecular weights M̄ w in the range 15,000–350,000 were prepared by a ring‐opening polymerization. The molecular weight distributions (MWDs) of these samples were determined by gel permeation chromatography (GPC). The method involves a universal calibration of the columns on the basis of polystyrene standards and a rapid iteration algorithm leading to the establishment of the Mark–Houwink relationship. In addition, osmometry and viscometry data are presented. The effect of hydrolytic degradation on the MWD of two PLA samples was studied by GPC.