Effects of Polymer Molecular Weight and Ceramic Particle Size on Flexural Properties of Hydroxyapatite Reinforced Polyethylene

Abstract

Hydroxyapatite (HA) reinforced polyethylene (PE) was the first bioactive ceramic-polymer composite developed for bone substitution on the basis of mimicking the structure and matching properties of bone. Both biological and mechanical properties of this material have been extensive studied. To understand the behaviour and determine mechanical properties of HA/PE composite under the bending condition, flexural tests of the composite were conducted in this investigation. It was found that an increase in HA volume percentage led to a corresponding increase in flexural modulus of the composite. Flexural modulus values were at the same levels as those of tensile modulus at different HA volume percentages. Generally, a larger HA particle size in the composite resulted in a lower flexural modulus of the composite. The fracture mechanism of HA/PE composite in the bending mode was the same as that for other hard particle filled polymers.