POLY(DL-LACTIDE)/HYDROXYAPATITE COMPOSITE: (Ⅳ)SURFACE MODIFICATION OF HYDROXYAPATITE AND ITS EFFECT ON THE INTERFACIAL INTERACTION OF THE COMPOSITES

Hydroxyapatite particles were modified by 3-(trimethoxysilyl) propyl methacrylate (A-174) and polyacrylic acid (PAA) in aqueous solutions respectively. Poly(DL-lactide)/hydroxyapatite(PDLLA/HA) composites were prepared by solution-dispersion compounding and composites rods with diameter 3.2 mm were achieved by oriented molding. Results showed that the glass transition temperature of PDLLA in composites and the bending strength of the composites were increased because of enhancement of the interfacial bonding of the composites.