Polylactic Acid for Surgical Implants

LACTIC acid in its racemic or optically active form can undergo acid catalyzed homopolymerization to yield a polymer of lower molecular weight, which is not suitable for plastic or fibers.¹ However, the cyclic diester, the lactide² of lactic acid, can polymerize by anionic ring opening addition mechanism under the influence of catalysts to a high polymer, which can be cast into strong films or spun into fibers^3-6 comparable to the industrial polyesters like dacron. This property, and in addition, the possibility of this polyester undergoing hydrolytic de-esterification finally to the lactic acid, which is a normal intermediate in the lactic acid cycle of the carbohydrate metabolism, make this a highly interesting product as a synthetic surgical repair material possibly for vascular grafts and sutures. Moreover, the material is expected to elicit no immunological response due to the absence of peptide linkages. No literature references, however, are available