High performance composites containing perfluoropolyethers-functionalized carbon-based nanoparticles: Rheological behavior and wettability

Ultra High Molecular Weight Polyethylene (UHMWPE) based composites filled with carbon nanotubes (CNTs) and carbon black (CB) modified by perfluoropolyethers (PFPE) have been formulated. All composites show a segregated morphology with nanofillers selectively localized at the polymer particle-particle interface. The composites rheological properties have been deeply investigated: the PFPE functionalities linked on CNTs facilitate the semi-3D nanofillers network formation in the composites that show a solid-like behaviour even at lower investigated filler contents, reaching the rheological percolation threshold at lower nanofiller content than bare CNTs filled composites. For composites containing CB, the presence of PFPE is useful to prevent the CB re-aggregation but does not significantly affect the rheological behaviour. Finally, the UHMWPE-based composites containing CNTs-PFPE and CB-PFPE show tunable wettability, due to the inherent hydrophobicity of PFPE chains.