A NOVEL-APPROACH TO POLYMERIC MICRODISPERSIONS

Novel microdispersions of one polymer in another have been created by solvent devolatilization. Two incompatible polymers are first dissolved in a common solvent. The solvent is then rapidly evaporated, causing the residual polymeric solution to enter the two-phase region. Depending on the relative amounts of the two polymers and the rate of evaporation, polymer blends of widely differing morphologies are formed. Unlike previous methods employed for their production, polymer dispersions created by devolatilization have remarkably uniform particles, with the average size controllable in the range of 0. 5 mu m to 20 mu m. If the solvent free volume fractions of the two polymers are more or less equal, co-continuous networks are formed.