Recovery of bimodal particle size distributions with multiangle dynamic light scattering

Abstract

By using the multi-angle dynamic light scattering measurement and the weighted constrained regularization method, the four groups simulated particle systems with bimodal distribution(100/600 nm, 200/600 nm, 300/600 nm, 350/600 nm) were measured by selecting one, three, six and ten scattering angles respectively. The results of inversion of size distribution show that, by using the weighted constrained regularization method to inverse the multi-angle dynamic light scattering data of the particle systems with bimodal distribution, the bimodal particle size distributions with a peak position ratio less than 2:1 and containing large particles(>350 nm) can be attained. This conclusion was verified by the measurement results of the standard polystyrene latex particles. The reason to attain the bimodal particle size distributions of the large particles is that, the multi-angle dynamic light scattering can provide more particle size information of large particles, the weighted constrained regularization inversion method can reduce the noise of the measurement data. Therefore, the weighted inversion of the multi-angle dynamic light scattering measurement data can achieve the measurement of the bimodal particle systems with a peak position ratio less than 2:1 and containing large particles.