Ternary Polymer Solutions with Hydrogen Bonds, 1

The Flory Huggins methodology coupled to AET has been extended to ternary polymer systems, in particular to solvent (A)/polymer 1 (B)/polymer 2 (C) systems, with the two polymers displaying H-bonding interactions. Because the H-bonding can perturb the randomness of polymeric conformations, the change in Gibbs free energy of mixing, Delta G, should arise from changes in combinatorial entropy as well as in interaction energy. The combinatorial part of Delta G is evaluated through AET as a function of the association constant eta between B and C components, the autoassociation constant sigma between B components, and the independent number m of interaction sites of acceptor C. The enthalpic contribution is evaluated by introducing concentration independent interaction parameters,g(ij)', evaluated by subtracting from the functions g(ij)(phi) the energetic contributions due to the H-bonding specific interactions. Once the resulting resulting Delta G equation is tested, values obtained for hypothetic systems with low, moderate and strong H-bonding interactions are discussed.