A new method for measurement of encapsulation efficiency in silica/acrylic nanocomposite particles from miniemulsion polymerization

The synthesis of latex composite particles has recently acquired a growing interest due to the combination of properties of the composing materials. Surface modification of silica nanoparticles was performed chemically by using of glycidyl methacrylate (GMA) in an optimal level. Nanocomposite particles containing the above modified nanosilica were prepared through miniemulsion polymerization in the presence of methyl methacrylate (MMA)-butyl acrylate (BA)-methacrylic acid (MAA). Latex particle size and morphology were thoroughly investigated by DLS, SEM, AFM and TEM analyses. A new method using quantitative EDX was applied for indirect assessment of the encapsulation efficiency. Encapsulation efficiency of silica nanoparticles was found to be about 92%.