Development of polymer composites based on ultrahigh molecular weight polyethylene, polytetrafluoroethylene and carbon fibers

Abstract

The paper presents research results on the properties of polymer composite materials based on ultrahigh molecular weight polyethylene and polytetrafluoroethylene modified with carbon fibers.It has been established that an increase in CF concentration is accompanied by a decrease in the stress-strain properties of a PCM based on PTFE, as well as by a change in the behavior of tensile strain curves of the PCM. It has been found that the decrease in stress-strain properties and the change in the failure mode of PTFE-based composites containing CF of the LO-1-12N/40 grade occur at a concentration of 5 wt%, and with the introduction of fibers of the Belum brand, 10 wt% concentration is required. This is probably due to the different values of the critical volume content (φm) of CF in PTFE. It has been detected that the strength is increased by 80% at 5% compression of PCM, and it is doubled at 10% compression in comparison with unfilled PTFE. The rate of mass wear of the PCM based on PTFE containing discrete carbon fibers decreases with an increase in filler concentration.The prospects of using carbon fibers as a reinforcing element of UHMWPE with the aim of obtaining new composites with high tribotechnical characteristics intended for operation under conditions of limited lubrication or dry friction are shown. It has been established that, to improve the stress-strain properties and wear resistance of the PCM based on UHMWPE, it is efficient to use carbon fiber of the Belum brand as a filler, since the interphase interaction of UHMWPE with the fiber is strong due to a hydrophobic fluoroorganic coating on the surface of these carbon fibers.