Determination of particle size distribution and elastic properties of silica microcapsules by ultrasound spectroscopy

The acoustical properties of silica microcapsules synthesized by the interfacial polymerization of sodium silicate were studied by ultrasound spectroscopy. The experimental data were reproduced by the Waterman-Truell dispersion relation with the scattering function theory proposed by Goodman and Stern for hollow particles in liquid. The particle size distributions were successfully evaluated by the analysis and were found to be in good agreement with those obtained by scanning electron microscopy (SEM). The formation of such silicate microcapsules synthesized through water/oil/water emulsion as a template was also monitored. (C) 2016 The Japan Society of Applied Physics