Carbon nanofibre‐reinforced ultrahigh molecular weight polyethylene for tribological applications

Abstract

Carbon nanofibre (CNF)-reinforced ultrahigh molecular weight polyethylene (UHMWPE) nanocomposites containing up to 10 wt % of nanofibres were prepared by a novel solvent-assisted extrusion process using short chain oligomers to tailor the melt viscosity of the UHMWPE matrix. A detailed investigation of the resulting nanocomposite microstructure and of the static mechanical properties revealed that the carbon nanofibres lead to improved mechanical properties of the UHMWPE related to the wear performance of such systems. Unidirectional sliding tests against a 100Cr6 steel under dry conditions verified the significant potential of dispersed carbon nanofibres to reduce the wear rate of this polymer. In light of the promising results, a further optimization of the processing conditions of such UHMWPE nanocomposites is expected to yield interesting future nanocomposite materials even for demanding applications such as artificial knee implants.

Wear Performance of UHMWPE and Reinforced UHMWPE Composites in Arthroplasty Applications: A Review

“…In Xu's study, the addition of 0.5 wt% CNF resulted in an improved wear resistance, while a higher level CNF addition (3 wt%) resulted in a higher wear rate [64]. A similar trend was found in Galetz's study [62], in which with 5 wt% CNF, the nanocomposite showed a highly improved wear rate compared to the pure UHMWPE. Compared with 5 wt% CNF-reinforced UHMWPE, the wear rate increased at the presence of a larger CNF concentration (10 wt%).…”

“…Studies on the mechanical properties of CNF reinforced polyethylene revealed that the material's yield stress, tensile modulus and hardness increased by the addition of a certain amount of CNFs. For example, it was reported that incorporation of 5 wt% CNFs resulted in an approximately 25% increase in the tensile modulus, while increasing the CNF content to 10 wt% led to a slightly additional benefit [62]. Similar trends were also observed for the hardness of CNF reinforced UHMWPE material [62].…”

“…For example, it was reported that incorporation of 5 wt% CNFs resulted in an approximately 25% increase in the tensile modulus, while increasing the CNF content to 10 wt% led to a slightly additional benefit [62]. Similar trends were also observed for the hardness of CNF reinforced UHMWPE material [62]. The addition of the carbon nano-fibres results in an approximately linear increase in hardness.…”

“…Due to the complexity of UHMWPE material, the incorporation of CNF or CNT into UHMWPE is greatly complicated by the extremely high viscosity of the polymer matrix. The agglomerations of carbon nanofillers with a size of several tens of microns could act as localized stress concentration points [62]. These weak points could be removed from the bulk material in a wear process, resulting in wear particles.…”

Effect of Wood-derived Charcoal Content on Properties of Wood Plastic Composites

“…You & Li 24 reported that the incorporation of bamboo charcoal flour into the polyethylene improved the elastic recovery and decreased the recovered strain remarkably. Carbon-based fillers act as a solid lubricant reducing the coefficient of friction 25 , while also potentially improving other mechanical properties of the thermoplastic composites 26,27 .…”