Effect of filler on kinetics and energy of activation of phase separation in poly(methyl methacrylate)/poly(vinyl acetate) blend

Abstract

The effect of a filler on the rate and energy of activation of phase separation was studied for binary poly(methyl methacrylate)/poly(vinyl acetate) blends (system with LCST) using light scattering. It was found that the rate of phase separation of the filled blends at close quench depth AT = T-T s is much lower as compared with the unfilled one at close quench depth. The activation energy for the filled blends is lower than that of unfilled blends. The drop of the rate of phase separation and of the activation energy in filled systems is explained by the formation of a border layer at the interface with solid where molecular packing is less dense and molecular mobility is restricted in comparison with unfilled polymer. Equal rates of phase separation or the equilibrium state may be achieved at higher quench depth for the filled blend.