Development of Biocompatible HA/PMMA Nanocomposite Membranes

Abstract

Much of the efforts have been put in the development of biomaterials for the replacement of bones. During the past years there has been a tremendous increase in the use of biomaterials for bone related surgical applications. Presently the use of biomaterials is restricted by their low mechanical properties. Efforts are being made during this study to develop membranes of polymethyl methacrylate and bioactive hydroxyapatite having excellent biocompatibility and osteoconductivity along with improved mechanical properties. Hydroxyapatite (HA) is synthesized by wet precipitation method to obtain nano sized particles by the reaction of calcium and phosphate precursors. These PMMA/HA composite membranes are prepared by making separately solution of PMMA in chloroform and dispersion of n-HA in distilled water. This solution and dispersion is mixed and then stirred to achieve the maximum dispersion. This solution is then casted in Teflon molds for solvent extraction. The membrane are then removed after complete extraction of the solvent. The HA concentration is varied to get multiple membranes. The biocompatible membranes are successfully prepared and characterized. SEM analysis shows the fine dispersion of n-HA particles in polymer matrix. XRD and FTIR shows no phase change in HA. The composite membranes were also tested under tensile test that shows enhanced mechanical properties i.e. tensile strength and hardness increases with increasing amounts of HA. Incorporation of HA particles in PMMA matrix also showed improved thermal properties which are in agreement with the TGA and DSC results. Moreover it shows no significant absorption of water. Obtained properties are suggestive of being used for bone fixation and potential surgical application. As the amount of HA increases, the properties of the membrane also improve. Tensile strength increases and it absorbs less water content which makes it more suitable to be used as a barrier membrane in the orthopedics and dentistry. But after certain amount of HA, the properties show decline in their trend