Fabrication of polymethyl methacrylate/polysulfone/nanoceramic composites for orthopedic applications



We report the fabrication of polymethyl methacrylate/polysulfone/nanohydroxyapatite (PMMA/PSu/nHA) and PMMA/PSu/nanotitania (PMMA/PSu/nTiO2) composites using NN′-methylene-bis-acrylamide (MBA) to crosslink PMMA and act as a blending agent. The composite was made porous by incorporating polyethylene glycol as the pore-forming agent. The blend between PMMA and PSu was confirmed using Fourier transform infrared spectroscopy and thermogravimetric analysis (TGA). The surface morphology of the composites analyzed using scanning electronic microscopy (SEM) revealed the porous structure and the wide distribution of the fillers that were found to aggregate at higher concentrations. The maximum tensile strength observed for composites was with 5% nHA (23 MPa) and 7.5% TiO2 (30 MPa). The TGA of the composites showed better thermal stability with increase in the filler concentrations. The X-ray diffraction analysis showed that appearance of new peaks in the blend polymers indicating a strong interaction between PMMA and PSu. The surface of the composites was coated with amoxicillin and its efficiency was examined by the Zone of Inhibition test using Streptococcus mutans. The bioactivity of the composites was evaluated by immersing them in simulated body fluid and examining their surface for the formation of calcium-phosphate layer using SEM and EDAX. Bioactivity was found to increase with increase in filler content. The in vitro biocompatibility of the composites, evaluated using monkey kidney epithelial cells by MTT assay showed that the composites containing nHA showed better cell viability than the composites with nTiO2. The study showed that the composites with nTiO2 exhibited better strength when compared with nHA composites while the later exhibited better biocompatibility. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013