Polymer nanocomposites with enhanced performances are becoming a trend in the current research field, overcoming the limitations of bulk polymer and meeting the demands of market and society in tribological applications. Polytetrafluoroethylene, poly(ether ether ketone) and ultrahigh molecular weight polyethylene are the most popular polymers in recent research on tribology. Current work comprehensively reviews recent advancements of polymer nanocomposites in tribology. The influence of different types of nanofiller, such as carbon-based nanofiller, silicon-based nanofiller, metal oxide nanofiller and hybrid nanofiller, on the tribological performance of thermoplastic and thermoset nanocomposites is discussed. Since the tribological properties of polymer nanocomposites are not intrinsic but are dependent on sliding conditions, direct comparison between different types of nanofiller or the same nanofiller of different morphologies and structures is not feasible. Friction and wear rate are normalized to indicate relative improvement by different fillers. Emphasis is given to the effect of nanofiller content and surface modification of nanofillers on friction, wear resistance, wear mechanism and transfer film formation of its nanocomposites. Limitations from the previous works are addressed and future research on tribology of polymer nanocomposites is proposed.

This study is aimed at determining the interfacial adhesion strength (IAS) of kenaf fibres using different chemical treatments in hydrochloric (HCl) and sodium hydroxide (NaOH) with different concentrations. Single fibre pullout tests (SFPT) were carried out for both untreated and treated fibres partially embedded into three different polymer matrices; polyester, epoxy, and polyurethane (PU) as reinforcement blocks and tested under dry loading conditions. The study revealed that kenaf fibres treated with 6% NaOH subjected to polyester, epoxy, and PU matrices exhibits excellent IAS while poor in acidic treatment. The effect of SFPT results was mainly attributed to chemical composition of the fibres, types of fibre treatments, and variation in resin viscosities. By scanning electron microscopy examination of the material failure morphology, the fibres experienced brittle and ductile fibre breakage mechanisms after treatment with acidic and alkaline solutions.

In this current research, the mechanical, physical and tribological properties of kenaf fibre particle reinforced epoxy (KPafRE) composite was investigated. Randomly distributed kenaf fibre particles were used as reinforcement, with fibre particle loading up to 20%wt. Five mechanical tests were conducted: tensile, compression, flexural, hardness and impact tests, also an additional water absorption test. For tribology investigation, dry sliding test was conducted on a Pin on Disk (POD) machine under 5–20 N applied load at 2.8 m/s, for 6.72 km sliding distance. The results from these tests were compared with Neat Epoxy (NE). It was found that KPafRE composite showed improved mechanical properties compared to NE. The results also suggest that 15%wt. KPafRE composite is the optimum fibre particle loading condition. Applications for this composite would include for construction industry for parts such as sliding door and window panels, also hinges (replacing expensive aluminum ones currently in use). In the automotive industry, the composite could replace plastic parts currently being used in door linkages, dashboard or door aesthetic piece, also bearing or bushes.

To reduce the emission of harmful materials into the ecosystem, researchers have been exploring the potential of manufacturing polymeric composites based on natural fibres. Although the large area of application of these materials has encouraged investigations of their performance under various loading conditions, less research has been conducted on their tribological behaviour. Hence, in this study, tribological tests were conducted on epoxy composites based on bamboo fibres. The wear performance of bamboo fibre reinforced epoxy was tested using various operating parameters, and the worn surfaces were examined using optical microscopy. The results revealed that the specific wear rate of the composites reduced since the epoxy was reinforced with bamboo fibres. Scanning electron microscopy analysis showed different wear mechanisms and damages.

The present work aims at exploring the possibility of using sustainable kenaf particles as particulate fillers and reinforcement in epoxy (KPafRE) composites. Kenaf particulate fillers of weight fractions (5–20 wt%) were used as reinforcement in the study of wear and friction performance of the composites. Adhesive dry tests were conducted on a Pin-on-Disc machine at applied loads (5–30 N) subjected to a stainless steel counterface with a sliding velocity of 2.83 m/s through sliding distances (0–6.72 km). From the findings, it was discovered that 15 wt% of KPafRE composite experienced superior in wear and frictional properties; the specific wear rate and friction coefficient was reduced by 67% and 56%, respectively, as compared to neat epoxy. Photo micrographs of the worn samples revealed that there was a significant amount of back film transfer, which assisted in enhancing the wear and frictional performance of the composites.

The present work is an attempt to investigate the mechanical properties of a treated betelnut fibre-reinforced polyester composite. Tensile, flexural, compression, and hardness tests were carried out. As a result of reinforcing the polyester with the treated betelnut fibre mats, the tensile, flexural, compression, and hardness properties of the composite were enhanced by about 141 per cent, 28 per cent, 85 per cent, and 6 per cent when compared to neat polyester. The high roughness of the outer layer of the treated betelnut fibre and the presence of trichomes were the main reasons for the high enhancement of mechanical properties of the composites. Scanning electron microscopy observation showed low fibre pullout during the mechanical test. The failure mechanism was dominated by fibre breakage and slight debonding during the tensile tests.