Preparation and Characterization of a Poly(methyl methacrylate) Based Composite Bone Cement Containing Poly(acrylate-co-silane) Modified Hydroxyapatite Nanoparticles

The purpose of this study was to study the mechanical properties of poly(methyl methacrylate) (PMMA)-based bone cement incorporated with hydroxyapatite (HA) nanoparticles after surface modification by poly(methyl methacrylate-co--methacryloxypropyl timethoxysilane) [P(MMA-co-MPS)]. PMMA and P(MMA-co-MPS) were synthesized via free-radical polymerization. P(MMA-co-MPS)-modified hydroxyapatite (m-HA) was prepared via a dehydration process between silane and HA; the bone cement was then prepared via the in situ free-radical polymerization of methyl methacrylate in the presence of PMMA and P(MMA-co-MPS)-m-HA. Fourier transform infrared (FTIR) spectroscopy, H-1-NMR, and gel permeation chromatography were used to characterize the P(MMA-co-MPS). Thermogravimetric analysis and FTIR were used as quantitative analysis methods to measure the content of P(MMA-co-MPS) on the surface of HA. The effect of the proportion of m-HA in the PMMA-based bone cement on the mechanical properties was studied with a universal material testing machine. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was also carried out to determine the cytotoxicity of the composite bone cement. The results showed that the surface modification of HA greatly improved the interaction between the inorganic and organic interfaces; this enhanced the mechanical properties of bone cement for potential clinical applications. (c) 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40587.