Расслаивающиеся полимерные растворы в микроразмерных порах: фазовые переходы, индуцированные деформацией пористого материала

Abstract

The influence of pore morphology on phase equilibria in stratifying polymer solutions within porous matrices has been simulated by means of equilibrium chemical thermodynamics. Using the example of liquid stratifying polybutadiene-polystyrene oligomer mixtures, we have shown that deformation of a matrix which influences on pore shapes, determines mutual solubilities of components within a pore, equilibrium volume ratios of co-existing phases and their thermodynamic stability. The change in the geometric characteristics of a pore is simulated in general by introducing a parameter corresponding to the degree of deviation of the shape of the pore walls from the spherical one. The dependences of mutual solubilities of components on pore volume within pores of different shapes are different which has been explained by the existence of several mechanisms of lowering the free energy of the system. Severe deformations of a matrix lead to suppressing the stratification in microsized pores while every composition up to the equimolar one becomes thermodynamically stable.