Wear-resistant and transparent acrylate-based coating with highly filled nanosilica particles
writer:Hui Zhang, Hui Zhang, Longcheng Tang, Zhong Zhang*, Lei Gu, Youzhong Xu, Christian Eger
keywords:Silica nano particles, Nanocomposites, Hybrid coating, Wear resistance
source:期刊
specific source:Tribology International
Issue time:2010年
Hybrid nanocoatings are one of the most attractive topics in nanomaterials which have achieved the
transition from fundamental researches to practical applications. In the present study, a urethane–a-
crylate oligomer was mixed with varied concentrations of nanosilica particle sol, spin-coated onto
polycarbonate substrate and finally cured by ultraviolet (UV) rays. The morphology, mechanical
properties and wear resistance of the resultant hybrid coatings were systematically investigated.
Infrared spectroscopy (IR) analysis was performed to determine the eventual curing extent of the
mixtures studied. The transmission electron microscopy (TEM) micrographs revealed almost perfect
dispersion of the nanosilica particles within organic matrices, which ensured the excellent transparence
of the hybrid coatings. Nanoindentation was further conducted to determine the mechanical properties,
i.e. hardness, elastic modulus and their nanoparticle loading dependence. The short-term wear
resistance was characterized by a pencil hardness tester. Moreover a universal micro-tribotester (UMT)
was applied to investigate the long-term performance. As a result, about 20% decrease in coefficient of
friction (COF) was achieved by the coating filled with 40 wt% nanosilica particles, compared to that of
the unfilled coating. Under the same fretting test conditions, the wear rate in terms of wear volume of
the hybrid coating containing 40 wt% nanoparticles was about 70 times lower than that of the neat
coating, confirming the wear-reduction capability of the nanoparticles. The related wear mechanisms
were discussed based on worn-surface observations.