Preparation and characterization of biodegradable thermoplastic Elastomers (PLCA/PLGA blends)

A biodegradable elastomer (PLCA/PLGA blends) was prepared and characterized. First, poly(DL-lactide-co-epsilon-caprolactone) (PLCA) and poly(DL-lactide-co-glycolide) (PLGA) were synthesized. Infrared (IR) spectroscopy, H-1 nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC) were used to confirm the formation and structure of PLCA and PLGA. The solubility parameters of PLCA and PLGA were measured to estimate the miscibility between them. A series of PLCA/PLGA blends was prepared through solution blending. The morphology of all blends was examined by scanning electron microscope (SEM), and no obvious phase separation was detected at various ratios of PCLA and PLGA. Thermomechanical properties were characterized using thermogravimetry (TG), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA), the results showed that the PLCA/PLGA blends were a type of immiscible but compatible polymer blend. Mechanical properties, particularly stress-strain behavior, were examined; with an increase in PLGA content, the tensile strength and Young's modulus of the blends increased dramatically, while elongation at break decreased.