D-Lactic Acid → D-Lactic Acid

Participants

Reaction Steps

Forty mg of d-lactic acid (Sigma-Aldrich, St. Louis, Mo.; catalog no. L0625) was polymerized in a microwave oven according to the method of Pandey and Aswath (J Biomater Sci Polym Ed. 2009; 20(1):33-48). Briefly, d-lactic acid was transferred to 2 ml Reacti-Vials (Pierce Chemical Co., Rockford, Ill.) and the polymerization was carried out vented in a GE Spacemaker Model JVM 1650WH05 (Serial #900524B; manufactured April 2006) with an RF output frequency of 2450 MHz in the absence of any added solvent or catalyst. Polymerization was carried out starting at Power 1 setting on the microwave and weighing at 30 second intervals. Power setting was increased stepwise until about Power 4 which resulted in a sample weight of 20 mg corresponding to 50% weight loss. Weight loss was from water during polymer esterification and dehydration. During the course of the microwave process, d-lactic acid crystals undergo a state change from a solid to a liquid and then to a gel at the end of the process. Similar procedure was used to produce PLLA with l-lactic acid.

Provenance & Evidence