Phase Separation and Gelation in Gelatin Gels

Abstract

We present evidence for the existence of phase separation in gelatin gels having methanol-water mixtures as the gel fluid. The curves for the liquid-gel transition and the spinodal line were determined using measurements of viscosity and of scattered or transmitted light intensity, respectively. For the 30%-methanol-water mixture, the gelation curve terminates at the critical point. We also analyze the observed phase equilibria of the gels with a simple mean-field theory.