▎ 摘　　要

The mechanical properties of PVC, ultra-high-molecular-weight PE, and a tetrafluoroethylene-vinylidene fluoride copolymer (F-42V) obtained by pressing polymer particles with an electrically conductive graphene coating have been studied. Cylindrical samples were tested for compression. At concentrations up to 2 wt %, graphene has little effect on the properties of ultrahigh-molecular-weight PE and vinylidene fluoride. On the contrary, the strength of PVC decreased by about a factor of four already at a graphene concentration of 0.5 wt %, and brittle fracture of the samples occurred. A further increase in the concentration of carbon particles almost did not alter the mechanical properties of the composite. The fracture surface of the composites had a granular structure corresponding to the shape of the initial polymer particles. In PVC matrix composites, a failure mechanism of cylindrical specimens, called cup-cone fracture, was observed. Such fracture was previously observed for ductile metals in tension or brittle marble in compression. The data obtained allow the conclusion that the mechanical properties of the composite are determined mainly by the polymer matrix. During molding, the graphene coating cracks and form folds according to the mechanism of buckling of a beam on elastic foundation. The cracks are oriented perpendicular to the direction of particle elongation, while the folds are oriented along them.