Tribology of Polymers and Polymer Composites
In the 21st century, researchers have shifted towards self-lubrication approaches to reduce friction and wear where external lubrication cannot be used. Therefore, the researchers have used the polymer and its composites as protecting layers in engineering components because it gives a better self-lubricating property and is easy to apply economically. Further, it can be used as bulk, coating, and composites where friction, wear and surface-related properties are effectively utilized. But, due to its poor mechanical properties and thermal stability, restricted to use in many engineering applications. To improve these properties, the researchers have added solid fillers such as graphite, graphene, MWCNT, MoS2, etc. and liquid fillers such as perfluoropolyether and base oil as reinforcement. After adding fillers, an improvement in thermal, mechanical and tribological properties was observed compared to the pristine polymer. Furthermore, adhesive, abrasive, fatigue, delamination, and plough wear mechanisms have been observed in the polymer and its composites because its surface asperities undergo elastic, plastic, and visco-elastic deformation. Moreover, it was observed that the polymer and its composites are widely used to protect engineering surfaces in various applications such as low load bearing, microelectromechanical systems (MEMS), bio-medical, tyres, shoes, brakes, gears, etc. Further, it is essential to study polymer's thermal, mechanical and tribological properties and its composites for various applications. The summarized information about polymer and its composites is shown in Figure 1. Therefore, the unique collection is focused on published articles on the polymer and its composites for the betterment of the researchers interested in working on this research area.