X-ray powder diffraction quantitative analysis of an amorphous SiO₂-poly(methyl methacrylate) nanocomposite

Quantification of individual phases within a multiphase amorphous material has been achieved using a newly developed technique based on X-ray powder diffraction. The quantification method was developed during a study of an amorphous silica-poly(methyl methacrylate) (SiO₂-PMMA) hybrid nanocomposite. The efficiency of the method as a quantifying tool for individual phases was demonstrated for samples of SiO₂-PMMA prepared either by polymerization of methyl methacrylate in the presence of amorphous SiO₂ or by mechanically mixing known quantities of the individual and pre-prepared SiO₂ and PMMA materials. The weight percentages of amorphous SiO₂ in the nanocomposites as determined by application of the new technique were analogously found to be 29%, a result that was supported by thermogravimetric analysis and helium picnometry measurements.