Mechanical Poperties Of Methacrylic Acid Coupled TiO₂/PMMA Denture Base Resin

Objective:To study the effect of methacrylic acid (MAA) coupled withTiO2on the mechanical properties of self-curing resin.Methods:After activation of TiO2its structural characterization was tested by usi-ng Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction(XRD). Then nano-TiO2/PMMA and nano-TiO2/PMMA compoundedwith resin were constructed through insitu polymerization method. Thesesamples were divided into different groups according to the existence ofMAA and the concentration of TiO2inside.Transmission Electron Microsc-ope(TEM) and electronic universal testing machine were utilized to evaluateTiO2dispersion in the PMMA matrix and the mechanical properties of nano-composite resin.Results:1.In the monomer/water partitioning experiment,the n-TiO2dispeared ininterface of MAA and water at room temperature with a tendency towardwater. The coordination of meth-acrylicacid to the surface of the n-TiO2, thefunctioned n-TiO2exhibited good dispersion in the monomer organic phase.2.The powder X-ray diffraction patterns, as described in previous work showed that the TiO2still exhibited anatase.TEM resultsdisplayed a better TiO2dispersion in activated PMMA matrix. The IRspectrum confirmed that the carboxyl group of methacrylic acid has beencoordinated to thetitania surfacethrough the bridging bidentate mode.3.Mechanics assay showed a descending trend of self-curing resins mechan-ical properties along with the increase of TiO2amount while this relativelytrend can be mitigated by the adding of oupling agent.Conclusion:1.The functionalized n-TiO2exhibited high hydrophily and have bidentatecoordination between titanium atoms and the carboxylic groups ofmethacrylic acid, both n-TiO2and functionalized n-TiO2were anatase.2.An excellent distribution of the filler in the polymer matrix was observedbecause of using MAA as a couple agent.3.The machanical properties decresed with increasing of the concentrati-on of TiO2.4.Functioned-TiO2/PMMA nanocomposites presented better propertiesthan TiO2/PMMA nanocomposites at the high concentration.