Shape memory properties of poly(D,L-lactide)/hydroxyapatite composites.

Poly(D,L-lactide) (PDLLA) and Hydroxyapatite (HA) are compounded, which possess biodegradation, biocompatibility and shape memory properties. In the paper, we prepared serial imposing shape memory composites with different shapes, composite ratios and sample thicknesses. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) were carried out to examine surface morphology, glass transition temperature (Tg), dynamic mechanical properties, and shape memory effect of PDLLA/HA composites, respectively. Moreover, some interesting shape memory behaviors were investigated. The results show that the better disperse morphology of HA grains using the experiment methods, and PDLLA/HA composites at a definite range of compound ratio have much better shape memory effect than pure PDLLA polymer. It indicates that HA particles can improve shape memory effect and PDLLA/HA composites are potential for biomedical applications.