Dispersion behavior of fine particles in a highly viscous fluid under shear flow

摘要

A homogeneous or controlled dispersion of fine particles into a polymer material has been demanded for producing a polymer composite. The clarification of particle behavior under a simple steady shear flow is useful to understand the mechanism and to invent novel methods of particle dispersion. In this research, the dispersion behavior of the mixture consisting of silica fine particles and a highly viscous molten polymer when applying shear in a cone-plate apparatus was investigated. As a shear applied to the mixture, the agglomerates were broken up and the particles agglomeration approached a steady state. In a dispersing process, the averaged agglomerated number of particles could be well correlated by a strain, which is amount of deformation of the mixture. Further, the relative viscosity of the agglomerated mixture to the dispersed one will be a good index to indicate the particle agglomeration.