Surface-modified biphasic calcium phosphate/poly (L-lactide) biocomposite

Abstract

Biphasic calcium phosphate (BCP) powders were prepared by hydrolyzation process and surface-modified by directly grafted L-lactide (LLA) onto the surface of BCP through a chemical linkage. The grafting ratio of organic groups was 9 wt%. After surface modification, the surface of BCP powders was covered by the lamella-shaped crystal. Poly (L-lactide) was mixed with BCP to form the BCP/PLLA biocomposite. Modified BCP (mBCP) particles could be uniformly dispersed in PLLA matrix. The compressive strength of the mBCP/PLLA composite is 115 MPa, 28% higher than that of unmodified-BCP/PLLA composite. The improved mechanical strength is attributed to the enhanced adhesion between the inorganic BCP filler and the organic PLLA matrix.

Keywords

biphasic calcium phosphate (BCP) / surface modification / grafting / composite / poly L-lactide

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