Adhesives as polymer blends

Specific features of the phase equilibrium in adhesive compositions based on polymer blends are considered. It is shown that polymer blends can be characterized by structures of three types: a single-phase system in the case of complete mutual solubility, the dispersion of one polymer in a continuous matrix of another polymer, and a two-phase continuous system (interpenetrating networks). Some problems of the kinetics and thermodynamics of polymer dissolution in a polymeric medium are considered for each of the aforementioned three types of structures. It is established that the final structure of a polymer blend after the evaporation of solvent is determined by the kinetic potentialities for the attainment of thermodynamic equilibrium of the phase state. The dependence of the structure on the solution viscosity is studied by the example of highmolecularweight butadiene-acrylonitrile rubber and epoxy resin in a mixture of acetone and toluene. Regularities of the formation of the phase structure of an adhesive that make it possible to guarantee the stability of article properties are revealed.