Mineral–Polymer Composites Based on Hydroxyapatite and Polyvinylpyrrolidone for Medical Applications

Hydroxyapatite (HA)–polyvinylpyrrolidone (PVP) nanocomposites with the HA/PVP ratio of 3.6–14.5 were synthesized by chemical precipitation from solutions of calcium nitrate and ammonium hydrogen phosphate in a PVP solution. The phase composition, size of coherent scattering regions, and size and morphology of HA particles were determined after heat treatment of the products of synthesis. The chemical interaction of the composite components was established by ESR spectroscopy on exposure to laser radiation at 355 nm.