Crazing as a method for preparation of polymer blends

Abstract

Publications on the development of a new universal method for the preparation of polymer-polymer blends are reviewed. This approach is based on the phenomenon of solvent crazing, which comes into play in the tensile drawing of polymers in the presence of adsorption-active liquid media. It is important that solvent crazing is accompanied by the development of a unique fibillarporous structure, in which the dimensions of craze pores and fibrils do not exceed several tens of nanometers. Two approaches to the preparation of the polymer-polymer blends are described. According to the first approach, the nanoporous structure of the solvent-crazed polymer is filled with the monomer, and its further in situ polymerization results in the polymer-polymer blends. The second approach has been recently advanced by the authors of this publication; it involves direct penetration of macromolecules into the formed fibillar-porous structure of the solvent-crazed polymer. Both approaches are capable of producing diverse polymeric blends with a high degree of mutual dispersion of the components. The above materials are shown to be characterized by specific mechanical, electrical, and adsorption properties, which are due to the unique fibillar-porous structure of the solventcrazed polymer. The composition, structure, and properties of the prepared blends are controlled by the mechanism of solvent crazing and by the deformation conditions of the initial polymer. Several aspects of the practical application of the polymer blends prepared via the mechanism of solvent crazing in adsorption-active liquid media are reviewed.