Synergistic effects of hybrid graphitic nanofillers on simultaneously enhanced wear and mechanical properties of polymer nanocomposites

摘要

In this study, hybrids of organosilane-functionalized graphitic nano-materials, nanofibers (GNFs, 1-D) and nanoplatelets (GNPs, 2-D) were applied to fabricate high-density polyethylene (HDPE) nanocomposites with simultaneously enhanced wear and mechanical properties. Organosilane as a surfactant was shown to effectively assist the nanofiller–polymer matrix interactions, filler dispersion and distribution, GNP interlayer sliding motion, as well as the establishment of a filler network. The ratio of weight percentage (wt%) of silane coated onto GNP relative to GNF (defined as factor R) was adjusted by the amount of surfactant. The results indicated that hybrid nanofillers consisting of the GNF and GNP with the highest wt% ratio of silane coating on GNP compared to that of GNF suggested a synergistic effect on the improvements in both wear resistance and storage modulus of the nanocomposites. Compared to the pure polymer, the wear resistance of the hybrid GNF– GNP composite with the highest factor R was improved by 89%; the storage modulus was increased: up to 70% at -70 °C, and 83% at room temperature.