New Phase Transition in Polymer Solutions with Multicomponent Solvent

Considering the density-density correlation function of a concentrated polymer solution with multicomponent solvent we find a phase transition due to the heterogeneity of excluded volume constant. This new phase transition implies a strong enhancement of the scattered light intensity in the critical region, which can explain a recent experiment showing strong light scattering from a ternary polymer system consisting of polyethylene oxide (PEO) dissolved in nitroethane and 3methyl-pentane.