Light-curable composite of siloxane/hydroxyapatite prepared by the sol–gel process for bone defect treatment

The light-curable composite of siloxane/hydroxyapatite (HA) had been successfully achieved by photopolymerization of a kind of gel combined tetraethoxyorthosilicate (TEOS) and 3-methacryloxypropyltrimethoxysilane (MAPS) with siloxane-modified nano-HA (HA- g -Si). HA- g -Si was prepared by grafting reaction of 3-isocyanatopropyltrimethoxysilane (IPS) onto the surface of HA. Then, TEOS and MAPS were mixed as precursor, and photoinitiator 2-hydroxy-4′-(2-hydroxyethoxy)-2-methylpropiophenone (Irgacure 2959) and as-prepared HA- g -Si were added into the precursor to form a homogenous and sticky gel. The movable gel that could be cured with UV light resulted in various sharp immovable composites of siloxane/HA in different mold. The HA, HA- g -Si nanoparticles, and composites were analyzed by Fourier transformed infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, scanning electron microscopy, mechanical testing, and water contact angles. It could be a promising bone repairing material for orthopedic application. POLYM. COMPOS., © 2011 Society of Plastics Engineers.