Ultrasonic resonant scattering analysis of particle assembly supraball

When ultrasonic waves with the wavelength equivalent to that of the particles in suspension are incident on the particles, the frequency spectrum of the ultrasonic attenuation coefficient exhibits a resonance peak. This peak frequency depends on the elastic modulus and particle size of the particles. Elastic modulus analysis has been performed for spherical particles with uniform density using the ultrasonic spectroscopy (US) method, but particle assemblies have not been investigated. The particle assemblies, supraballs and SBs, have a larger specific surface area than spherical particles and are expected to be utilized in various applications. The rigidity of SBs is also important information for the mechanical stability of these particles. Therefore, in this study, we investigated the particle resonant scattering of SBs. The frequency dependence of scattering attenuation of SBs in liquid was investigated using the US method, and it was found that SBs with different rigidity could be obtained depending on the drying temperature and type of solvent and that their elasticity reflected the properties obtained by the US method.