Effect of Initial Dispersion State on the Structure and Property of Polymer Nanocomposites

Abstract

In the colloids-polymer mixture system, the microstructure of particles and polymers are strongly dependent upon their interactions, which can vary systemically with the component concentrations. When the colloidal system is concentrated by solvent evaporation with drying, the continuous change of component concentrations also causes a continuous change in the interparticle interaction. Previous studies have focused on controlling the rate of evaporation or drying conditions of solutions to change the structure of polymer nanocomposite (PNC). In this study, we show how the initial dispersion of the colloidal system can influence the final structure and property of the PNCs. To vary the initial dispersion state, we first set different initial dispersion concentrations to find the effect of polymer and particle volume fractions on the interaction. We observed that a certain concentration range exhibited a stronger attraction due to the depletion attraction. Large clusters induced by a depletion attraction cause a shear-thinning behavior in viscosity. Second, we provide different storage time for particles to be aggregated. The longer for storage time, the higher the viscosity of the colloidal system.