Low-temperature micromechanical properties of polyolephin/graphene oxide nanocomposites with low weight percent filler

The effect of small impurities of reduced graphene oxide (rGO) on microhardness of polyethylene (PЕ) and polypropylene (PP) matrices and the reaction of these nanocomposites and initial polymers on the influence of localized load in the temperature range of 77–295 K were studied. When rGO was introduced, PE practically did not change its properties, whereas the introduction of 0.3 wt% rGO into the PP matrix was accompanied by a significant increase in microhardness, especially in the room temperature range (by approximately 70%). A transition to reversible deformation was detected when the indenter impressions applied in liquid and gaseous nitrogen at temperatures below the threshold (T < 174.5 K for PP and T < 226.5 K for nanocomposite PP + 0.3 wt% rGO) were not fixed on the surface of the samples after their heating in the measuring device to room temperature.