Nanocomposites based on polyurethane and modified montmorillonite: thermodynamic approach to reinforcement

Nanocomposites based on thermoplastic polyurethane and montmorillonite (Mt) modified with oligourethaneammonium chloride were synthesized. The nanocomposites were obtained by the method solution exfoliation. The influence of the filler content on the thermodynamic of interactions, physical and mechanical properties, the structure and morphology of the created nanocomposites was investigated. The investigations have shown that the free energy of mixing the filler and the matrix during the formation of the nanocomposites decisively determines the physical and mechanical properties of the created nanocomposites. In case of thermodynamic compatibility between the matrix and the filler, dense surface layers of the matrix on the filler, high-quality polymer-filler contacts in the system are formed, which leads to the creation of nanocomposites with increased parameters of physical and mechanical properties. Mt modified with urethane-containing compounds can form strong hydrogen bonds with the polar polymer matrix and this allow to exfoliate the Mt up to the plates