Effect of reduced graphene oxide amount on the tribological properties of UHMWPE biocomposites under water-lubricated conditions

Abstract

Ultra-high molecular weight polyethylene (UHMWPE) has been broadly utilized in hip and knee artificial implant due to its low friction coefficient, high wear resistance and good biocompatibility. However, some disadvantage properties such as low young's modulus and low load bearing, anti-fatigue capacity limit application areas and wear debris of UHMWPE components cause implant failure. For this reason, reduced graphene oxide (RGO) filler was produced by green synthesis with vitamin C and the influences of RGO filler content on the tribological performance under distilled water lubrication condition were investigated and had been correlated with microstructure. RGO filled UHMWPE biocomposites were fabricated by firstly liquid phase ultrasonic mixing and then hot press molding. The characterization and experiment results revealed that the wear behavior of UHMWPE/RGO biocomposites were not only affected by the lubricant and binder properties of RGO, but also restricted by the content of RGO filler. The RGO filled UHMWPE biocomposites exhibited a lower wear rate and friction coefficient in comparison to the unfilled UHMWPE. The biocomposite with 0.7 wt% of RGO showed good interfacial bonding strength and excellent wear resistance. Furthermore, fatigue wear tracks reduced significantly on the same biocomposite surface. High crystallite size and microhardness value of UHMWPE/RGO-0.7 biocomposite was caused destroy the tribofilm formed on the Al 2 O 3 counterface.

Tribo‐material based on a UHMWPE/RGOC biocomposite for using in artificial joints

“…Green dots represented the oxygen elements in the EDS maps. The dispersion of oxygen was very important because only RGOC had oxygen containing functional groups in the matrix 19 . The results obtained from the EDS analysis were compatible with XRD results.…”

“…The FE‐SEM images of wear tracks for the unfilled UHMWPE and all biocomposites shown in Figure 10. It could be seen that the worn surface of unfilled UHMWPE were thin grooves in the low‐magnified image but the cracked surface layer of the polymer showed that the dominant mechanism was fatigue wear in the high‐magnified image 19 . The low‐magnified image of UHMWPE/RGOC‐0.1 biocomposite showed relatively flat surface but fatigue wear tracks were seen in the high‐magnified image.…”

“…GO was prepared from natural graphite (powder ~45 μm, Aldrich) by the modified Hummers method 16,17 and GO reduced with vitamin C to RGOC according to literature 18 . The detailed information about the production process of UHMWPE/RGOC biocomposites were described in previous literature 19 . A series of the biocomposites were prepared with the mass ratios (RGOC:UHMWPE) of 0.1, 0.3, 1.0, and 2.0 weight % (wt%).…”

Influence of processing conditions on microstructural, mechanical and tribological properties of graphene nanoplatelet reinforced UHMWPE

“…In the case of -BM composites, the behaviour is similar above 0.5 wt% GNP content, the difference being that below this critical concentration, there is a relative maximum in hardness at around 5.2 HV, which corresponds to 25% increase with respect to the thermoformed samples containing PE alone. This effect of GNPs on hardness is very high compared to other PE matrix composites reinforced with GO (Colak et al, 2020;Pang et al, 2018;Vadivel et al, 2018), RGO (Colak et al, 2020) J o u r n a l P r e -p r o o f and the same filler GNPs (Aliyu et al, 2019). In general, this effect is explained by an improvement in mechanical response due to load transfer through the filler sheets.…”

A critical review on ultra high molecular weight polyethylene (UHMWPE) for prosthesis and implant functions

“…This approach was seen to be promising due to the efficient dispersion of GO sheets into the UHMWPE matrix, which will lead to increased wear resistance. Colak et al [27] developed RGO by green synthesis with vitamin C. The effect of RGO filler material on tribological performances under distilled water lubrication. Wear resistance property is magnified and composite with 0.7 wt% (RGO) optimum properties.…”