Morphological structures and tribological performance of unsaturated polyester based untreated/silane-treated halloysite nanotubes

In this study, pristine halloysite nanotubes (HNT) and silane-treated halloysite (s-HNT) particles were incorporated into highly crosslink unsaturated polyester (UPE) to explore the morphological structure and tribological performance of UPE-HNT nanocomposite. Wear resistance of cured UPE/HNT and UPE/s-HNT nanocomposites were systematically evaluated using block-on-ring (BOR) configuration against stainless steel counterpart under a certain dry sliding conditions. TEM micrographs revealed a uniform morphological dispersion of halloysite particles in the UPE matrix. Both pristine and silane-treated HNT particles induced a modest decrease in a specific wear rate and coefficient of friction of nanocomposites. There was a pronounce reduction in the specific wear rate of the polyester composites at more than 5 wt.% of halloysite. However, the addition of silane exhibited insignificant results especially at higher percentages of HNT. The investigation of worn surface morphology and wear mechanism of materials by using SEM is also discussed.