Bioactive hydroxyapatite-polysulfone composite for tissue replacement

Abstract

A new composite material consisting of hydroxyapatite (HA) and polysulfone (PSU) was produced and evaluated for potential medical applications. The HA/PSU composite containing up to 40vol% of particulate HA was manufactured via a standardised procedure which included drying, compounding, and injection or compression moulding. Defect-free composite samples (bars, discs and dumbbell specimens) could be obtained by injection moulding. Thick composite plates suitable for making fatigue specimens were compression moulded. Both compounded materials and moulded parts were assessed using various techniques. It was found that HA particles were well dispersed in the PSU matrix. Thermogravimetric analysis verified the amount of HA in the composite. Density close to the theoretical value could be achieved for the composite, indicating a void-free structure. Differential scanning calorimetry results indicated that the glass transition temperature of the polymer matrix was not significantly affected by the incorporation of HA. Rheological analysis revealed that PSU and the composite exhibited pseudoplastic flow behaviour at processing temperatures. It was shown that the hardness and modulus of the composite were increased with an increase in HA volume percentage.