Patent ID: 8748558

Claim:
A solvent-free, catalyst-free method for producing a biocompatible composition comprising: contacting a polyalkylene oxide having a molecular weight from about 200 to about 1000 with an aliphatic dicarboxylic acid for a period of time from about 0.5 hours to about 120 hours to form a mixture; stirring the mixture in the presence of an inert gas and an acid scavenger selected from the group consisting of chitosan, neutral alumina, basic alumina, activated charcoal, and combinations thereof, for a period of time from about 1 hour to about 72 hours, at a temperature of from about 20° C. to about 75° C., to adjust the pH of the mixture to a pH from about 3 to about 7; maintaining the mixture at a temperature from about −70° C. to about 85° C., and recovering a flowable aliphatic polyester macromer from the mixture, wherein the molar ratio of polyalkylene oxide to aliphatic dicarboxylic acid is from about 4:3 to about 2:1.