A novel approach of homogenous inorganic/organic composites through in situ precipitation in poly-acrylic acid gel

A new in situ precipitation technique was developed to promote high-affinity nucleation and growth of calcium phosphate in the polymer hydrogel. Poly-acrylic acid/ hydroxyapatite (HAP) composites have been prepared using template-driven reaction. Nano-sized hydroxyapatite particles were distributed within organic template homogenously, furthermore, inorganic particles were fine and uniform. A kind of specific product with the characteristic of fractal was also obtained. During the composite process, 3D network of organic matrices played an important role in the superfine interaction of HAP and hydrogel through the compartment-effect of interior of hydrogel. This method provides an efficient approach toward inorganic/organic nanocomposites with high-uniformity decentralization for biomimetic replant applications. This paper discussed the mechanism of compartment-effect, and the concept of in situ precipitation in gel was brought forward. SEM and TEM were employed in the analysis of the morphological characteristic of uniform inorganic/organic composites and inorganic minerals separated from organic template. SEM-associated EDS area analysis and TEM-associated EDS analysis were employed in the analysis of component characteristic of inorganic/organic composite and inorganic particles. X-ray diffraction was employed in the analysis of precipitation phase crystal structure of inorganic component.