Preparation and degradation study of poly(L-lactide-co- -caprolactone)(PLCL) films by -ray irradiation

Abstract

Biodegradable elastomeric materials that have previously been investigated include copolymers of lactide (LA) and ε-caprolactone (CL) [1]. Semi-crystalline polymer, such as Poly(L-lactide-co- -caprolactone) (PLCL), are non-homogenous with a two-phase system consisting of amorphous and crystalline regions. This self-reinforcement, also observed for natural rubber, is the origin of high tensile strength and maximal extensibility of this strain-crystalizable physical network. The rate of degradation of PLCL is dependent on their degree of crystallinity (polymer morphology) and their glass transition temperatures (Tg). Radiation, at times used for polymerization purpose, has also been used for sterilization purpose. Radiation causes changes to the morphological properties of polymers, and can thus be used as a method to control the rate of degradation. In present study, radiation-induced degradation of PLCL was investigated, as a preliminary study to find out the predominant factors in improving the heat stability. PLCL was irradiated with -ray in air at 25℃. Molecular weight, melting point and glass transition temperature were measured as a function of irradiation dose, and the mechanism of radiation induced degradation is discussed.