Recently large amounts of inorganic nanotubes (INT) and inorganic fullerene-like (IF) nanoparticles of WS 2 became available and a method for their dispersion was developed. In the present work the tribological properties of epoxy composites and biopolymer with nanoparticles of different geometries like platelets (2H), spherical IF and elongated INT were studied. Coefficient of friction and wear rate were measured under dry contact conditions using different tribological rigs. All the investigated nanocomposites demonstrate a reduction in coefficient of friction and wear rate, while the influence of the particles shape, concentration and experimental conditions was also observed. The reduced value of epoxy wear as a result of nanoparticles addition is indicative of the polymer strengthening and simultaneous decreasing of the epoxy brittleness.The biopolymer matrix of poly(3-hydroxybutyrate) (PHB) is one of the most extensively researched and utilized biodegradable and renewable thermoplastic polyesters. Among other properties, these nanocomposites show an improvement in both tribological and mechanical (hardness and modulus) properties with respect to pure PHB evidenced by friction and nanoindentation tests. The friction coefficient measured after 1000 cycles for pure PHB was μ = 0.5 compared to μ = 0.2 for PHB impregnated with 1 wt.% of inorganic nanotubes, indicating a 60% improvement.
