Hydroxyapatite reinforced polysulfone as a new biomaterial for tissue replacement

摘要

A variety of bioactive particle filled polymers have been developed for tissue replacement since the early 1980s. In this investigation, hydroxyapatite (HA) reinforced polysulfone (PSU) composites were produced and evaluated for potential medical applications. Composites containing up to 15volpercent of HA were studied at the preliminary stage. The HA/PSU composites were made through a standardised procedure by incorporating a commercially available HA powder into a polysulfone resin of medium viscosity that is suitable for injection moulding. Compounded materials and injection moulded parts were assessed using a variety of techniques. It was found that HA particles were well dispersed in the PSU matrix after the compounding process. Defect-free composite samples could be obtained by injection moulding. Thermogravimetric analysis (TGA) verified volume percentages of HA in the composites. Differential scanning calorimetry (DSC) results indicated that the glass transition temperature (Tg) of the polymer matrix was not affected by the incorporation of HA. It was shown through dynamic mechanical analysis (DMA) that the storage modulus of the composite was increased with an increase in HA content below approx 185 deg C which is Tg of the polymer, while tan delta was maintain at nearly the same level for all composites. It was established that water uptake reached an equilibrium after 7 days' immersion in distilled water for all composites and unfilled PSU. It was found that after 7 days' immersion in distilled water, the storage modulus of HA/PSU composite was decreased less than that of unfilled PSU.