Novel poly lactic acid composites containing beta -Ca(PO_3)_2 fibers

摘要

A new type of biomaterial for bone repair with modulus of elasticity close to that of natural bone was prepared using bioresorbable poly lactic acid (PLA) and high-strength beta -Ca(PO_3)_2 fibers treated with dilute NaOH solution. A mixture consisting of PLA dissolved by using methylene chloride and the fibers was dried at ambient temperature, and subsequently it was hot-pressed uniaxially at 180 deg C, resulting in fabrication of a PLA-composite containing beta -Ca(PO_3)_2 fibers. Almost no degradation in the bending strength was observed even when a large amount of the fibers (e.g., 60 wtpercent) was introduced, and the modulus of elasticity was increased effectively with increasing the fiber content. The bending test of the composites showed that very high energy is consumed for their fracture and that the fracture proceeds step by step, even beyond the maximum stress.