The mechanical and tribological properties of grafted LDPE-filled SiO2/PTFE composite

Abstract

In this article, low-density polyethylene (LDPE) rubber and silica (SiO2) particles were employed to modify polytetrafluorethylene (PTFE) simultaneously. The distribution and dispersion of LDPE and SiO2 particles in PTFE matrix can be adjusted by the wettability of SiO2 particles toward PTFE and LDPE, so as to achieve a simultaneous enhancement of toughness and modulus of PTFE. A unique structure with the majority of PTFE surrounded by SiO2 particles was first observed using maleic anhydride (MAH)-grafted LDPE, resulting in a dramatical increase in Izod impact strength as the rubber content in the range of brittle–ductile transition (4–16 wt%). The friction and wear properties were obviously improved with the addition of MAH-grafted LDPE regardless of the content of SiO2.