Effect of reflux temperature on synthesis of chitosan / nano-hydroxyapatite composites

Abstract

Effect of reflux temperature on synthesis of Chitosan / nano Hydroxyapatite composite In this study, effect of reflux temperature for synthesis of chitosan / Nano-hydroxyapatite composites was investigated. Chitosan / Nano-hydroxyapatite composites were synthesized using co-precipitation technique at different reflux temperatures of 30 0C (Room temperature), 70 0C and 90 0C. Chitosan, acetic acid, calcium hydroxide and phosphoric acid were used as starting materials. 70/30 weight ratio of chitosan / Nano-Hydroxyapatite composites was selected for the study. H3PO4 / acetic acid / chitosan solution was added at a rate of 3 ml/min using a burette into stoichiometric weight of Ca(OH)2 solution under vigorous stirring. The pH value of the solution was continuously monitored using a pH meter. The resulting suspension was refluxed and aged for 24 h while being stirred. The precipitate was filtered and washed with distilled water. This procedure was repeated for the selected reflux temperatures. The characteristics of nano hydroxyapatite, ceramic powder / chitosan composite were investigated by Differential Thermal Analysis (DTA), Fourier Transformation Infrared (FTIR) spectroscopy and X-ray diffraction (XRD). Particle size was determined by XRD patterns using Scherrer’s equation. It was observed that particle size increases with increasing the reflux temperature. Both the size and shape of HA crystals, SEM images shows that nano HA particles were dispersed in the Chitosan matrix and the surface become rough and more porous.