Preparation, Characterization and Biodegradable Characteristics of Poly(1,3-trimethylene carbonate-co-glycolide)

Abstract

Poly(1,3-trimethylene carbonate-co-glycolide) (PGCA) has been synthesized by ring-opening polymerization of 1,3-trimethylene carbonate (CA) and glycolide (GA) with stannous octoate as catalyst. The copolymers were characterized by 1 H nuclear magnetic resonance (NMR), 13 C NMR and differential scanning calorimetry. Water content and static contact angle of distilled water on the polymer surface were used to evaluate the hydrophobicity of the copolymers. There was no apparent difference in hydrophobicities of copolymers containing up to 30mol% GA. The biodegradation of PGCA was conducted in phosphate buffer solution at 37°C and in rats. The results indicated that the degradation rates of PGCA were higher than that of PCA and depended on the GA fraction in the copolymers. Furthermore, degradation occurred in the bulk when the GA content exceeded 20mol%. With less GA units the degradation became a surface reaction both in vitro and in vivo. These properties of PGCA may be useful in protein delivery systems.