Influence of the Filler Particles' Surface Morphology on the Polyurethane Matrix's Structure Formation in the Composite.

This article presents the surface morphology effect of silicon carbide (SiC) particles on the polyurethane binder's structure formation in a dispersed-filled composite. The difference in the morphology and surface relief of filler particles was ensured by the implementation of plasma chemical modification. As a result of this modification, the filler consisted of core-shell particles characterized by a SiC core and a carbon shell (SiC@C), as well as a carbon shell decorated with silicon nanoparticles (SiC@C/SiNP) or nanos (SiC@C/SiNW). The study of the relaxation properties of polyurethane composites has shown that the strongest limiting effect on the molecular mobility of boundary layer's chain segments is exerted by a highly developed surface with a complex relief of SiC@C/SiNP and SiC@C/SiNW particles. An empirical method was proposed to find the polymer fractions spent on the formation of the boundary, transition and bulk layers of the polymer matrix in the composite. It was shown that the morphology of the filler particles' surface does not affect the dependence of the boundary layer thickness on the filler's volume fraction. However, with an increase in the degree of surface development, the boundary layer thickness decreases.