A predictive approach of the influence of operating parameters on the size of polymer particles synthesized in a simplified microfluidic system

Abstract

Monodisperse and size-controlled spherical polymer particles were synthesized by in-situ photopolymerization of O/W monomer emulsions. Monomer droplets were produced without surfactant or pre-treatment at a needle tip in a simplified axisymmetric microfluidic device. The effect of the viscosity of the continuous phase on particle size was studied. The system operated in the dripping mode, at low Reynolds number. A dimensionless master curve describes particle diameter as a function of the needle inner diameter as well as velocity and viscosity ratios of continuous and dispersed phases. An empirical law predicts particle size. The normalized particle diameter depends upon the ratio of the capillary numbers of continuous and dispersed phases with an exponent equal to -0.22.