Hydroxyapatite Base Nanostructure Materials Controlled Design, Synthesis, Characterization And Its Performance Study

Hydroxyapatite exhibits good bioactivity, biocompatibility, nontoxic, osteoconductive, and ion-exchange properties, so it can be extensively applied in such as biomedicine and wastewater treatment. Along with the improvement of living standards, heavy metal ion pollution to the water resources more and more serious, preparation the new functional materials with strong absorption ability have caused the researchers concern nowadays, meanwhile inherent brittleness of HAP has limited its application. Thus, in this paper, we have further developed and enriched the preparation method of hydroxyapatite and its composites, and proposed some novel and controllable synthesized routes for the synthesis of hydroxyapatite-based hybrid with high specific surface and strong adsorption ability make it suitable for biomedicine and sewage treatment fields, in this dissertation, we utilize dual surfactant as structure-directed templates, polymer particles as the template of porous structure, and present a facile hydrothermal synthesis approach controllable synthesized hydroxyapatite/graphene oxide. Some progresses have been achieved in prepare the hierarchical hydroxyapatite structure, bioactivity and adsorption of heavy metal ions. The main research results are summarized as following:1. uniform band-shape HAP crystal and other morphologies of HAP have been prepared by using4-aminobenzenesulfonic acid (ABSA) and polyethylene glycol4000(PEG-4000) as structure-directed templates in isopropanol/water mixed solvents through changing the the mass ratios of PEG-4000to ABSA, the volume ratios of the solvents and hydrothermal reaction temperature, the obtained HAP materials display better bioactivity. The results indicate that dual surfactant template effect and the synergic interaction with solvents effect can play a key role in mediating nucleation and growth of HAP crystal.2. Porous Hydroxyapatite (HAP) monoliths with hierarchically adjustable surface textures have been successfully prepared by pouring the HAP precursors into the gap among the preorganized poly(styrene-methyl methacrylate-acrylic acid)(P (St-MMA-AA)) colloidal sphere arrays and followed by a simple calcinations processes. Herein, the as-obtained HAP monoliths can undergo distinct morphologies evolution by gradually altering the features of polymeric colloidal spheres. Moreover, we performed and evaluated the bioactivity for the prepared HAP monoliths in simulated body fluid (SBF) conditions, indicating the greatly enhanced in vitro bioactivity of the HAP monoliths. This should be attributed to the hierarchically porous features of HAP monoliths. More interestingly, HAP monoliths with specific porous can possess specific capability for removing toxic heavy metal ions such as Pb2+and Cd2+in aqueous solution. Therefore, it was indicated that the obtained HAP monoliths can be employed as a highly effective adsorbent for the removal of pollutants in wastewater treatment.3. Controlled assembly of graphene oxide (GO) into three-dimensional (3D) porous GO monolith can be obtained by a facile hydrothermal method. Herein, we choose the PVA as linker and strengthening agent, by changing the chain length and amount of the PVA, a novel kind of porous GO monoliths with fine-tuning pore channel and network architecture was obtained. We adopt a simple method using GO synthesized not only porous structures, but also3D graphene/HAP hybrid materials. HAP crystal combine with GO form a3D macrostructure materials, these3D architectures of GO and GO/HAP composites exhibit good biocompatibility have potential application in tissue scaffolds, drug-delivery, supports for catalysts, and as template for biocomposites.