The tribological behaviors of core‐shell n‐octadecane@TiO₂/epoxy composites

Abstract

In this work, the n-octadecane@TiO 2 particles with core-shell structure were successfully prepared via a sol-gel method in an oil-in-water (o/w) emulsion. The resultant core-shell particles were incorporated into epoxy matrix to prepare composites. Compared with pure epoxy and TiO 2 doped epoxy, the incorporation of n-octadecane@TiO 2 reduced the friction coefficient (COF) and wear rate of epoxy. According to the systematical investigation of the wear tracks on three samples and scars on their friction antithesis balls, it was speculated that the antifriction effect of core-shell additives on composites were mainly attributed to the mixture formed by the crushed n-octadecane@TiO 2. The mixture not only backfilled the tearing-like cracks on worn face generated by fatigue wear, but also promoted the formation of transfer film.

Improved tribological performance of epoxy composites containing core–shell PE wax@SiO2 nanoparticles

“…It indicates that adhesive and fatigue wear occurred on the worn surface of epoxy doped with low content additives, which also result in their large COF and wear rates (Figure 6). In our previous work, [ 39 ] the neat epoxy produced plenty of wear debris scattered on both sides of the wear track and there were deep furrows in the wear track, which suggests severe abrasive wear occurred at the interface between neat epoxy and GCr15 mating ball. However, there was no hard inorganic SiO 2 to aggravate wear, the neat epoxy had relatively lower COF and wear rates than PSE‐1.…”

“…The selection of loads and velocities is a reasonable compromise based on the rated speed of the tester, wear resistance of samples and empirical parameters in previous work. [ 39 ] If the load and velocity are too small, the difference among composites in tribological performances is not significant. While the large load and velocity would lead to a deeper wear track excess of the measuring range of the profiler, or even wear out the specimen.…”

“…All tests were run at dry friction and the ambient temperature (20–25°C and 40–45 RH%). The wear rates of the composites were calculated by the formula [ 39 ] : …”

“…In recent years, our group has developed various lubricating additives with core-shell structures, such as PTFE@phenolic resin, [33,34] PTFE@polyacrylate, [35] PTFE@SiO 2 [36][37][38] and n-octadecane@TiO 2. [39] The improvement of these core-shell particles on tribological properties of the polymer matrix, lubricating oil, or water is sufficient to support that coreshell particle formed by the anti-wear phase SiO 2 entrapping the lubricating phase PE wax will be an effective means to improve the tribological performance of the epoxy resin. However, the effect of PE wax @ SiO 2 particles incorporated in the epoxy matrix on tribological performances and their influencing mechanism have not been reported.…”

Improved tribological and thermo‐mechanical properties of epoxy resin with micro‐nano structured ZrO2/Ti3C2 particles

“…[11][12][13][14][15][16] Nevertheless, these fillers usually have some shortcomings while the wear resistance of epoxy composites are improved, such as greatly increased density in metal nanopowders/epoxy composites, limited improvement of wear resistance of TiO 2 /epoxy composites, high cost for graphene/epoxy composites, low chemical durability and strongly depended on the epoxy systems in WS 2 /epoxy composites. [17][18][19][20] It is therefore urgent demand to develop new type of functional fillers for improvement of wear resistance and other performance of epoxy resin.…”