ABSTRACT
108 The problem of calculating the phase diagrams for multicomponent reacting and non-reacting polymer systems has been formulated. To solve this problem, the concept of the free energy of phase separation (FEPS) was introduced. Calculation of phase diagrams implies global minimization of FEPS. A numerical algorithm for FEPS minimization and appropriate computer program were developed. This procedure was used to calculate phase diagrams for the ternary systems styrene/PS/PMMA, chloroform/PS/polybutadiene, and styrene/PS/polydimethylsiloxane. The calculated data were found to agree with experiment. We also calculated a phase diagram for a reacting multicomponent system (diglycidyl ether of bisphenol A cured by 2,6-diaminopyridine in the presence of polyurethane). Up to 1000 intermediate reaction products that appear during cure were taken into account as individual components. The van Krevelen theory was applied to calculating the solubility parameter and molar volume for the system components. Reasonable qualitative agreement between experimental data on the cloud point and numerical results was reached.
