Thermodynamic stability of poly(methyl methacrylate)-polycarbonate blends. Effect of history and structure

Abstract The effect of sample preparation method on structure and on the Gibbs free energy of mixing in poly(methyl methacrylate)-polycarbonate blends is discussed. Blends prepared from solutions containing a partially crystalline polymer-polycarbonate-are thermodynamically unstable over the whole range of composition, whilst blends prepared from melt represent metastable biphasic systems. Two contributions to the Gibbs free energy of mixing have been identified; one is given by the chemical nature of components, the other depends on their dispersity.