COMPOSITE BIOMATERIALS WITH CHEMICAL BONDING BETWEEN HYDROXYAPATITE FILLER PARTICLES AND PEG PBT COPOLYMER MATRIX/

In an effort to make composites from hydroxyapatite and a PEG/PBT copo lymer (Polyactive(TM) 70/30), chemical linkages were introduced betwee n the filler particles and polymer matrix using hexamethylene diisocya nate as a coupling agent. Infrared spectra (IR) and thermal gravimetri c analysis (TGA) confirmed the presence of Polyactive(TM) 70/30 on the surface of HA filler particles. The amount of chemically bound polyme r was 4.7 wt.%, as determined by TGA. The mechanical properties of the composites, that is, tensile strength and Young's modulus, were impro ved significantly by the introduction of a chemical linkage between th e filler particles and polymer matrix compared to control composites. This method provides an effective way to introduce chemical linkage be tween HA filler particles and a polymer matrix. By optimizing the graf ting process, a further improvement of the mechanical properties in th e composites can be expected. (C) 1998 John Wiley & Sons, Inc.