The anticorrosion behavior and mechanism of Ti3C2 nanosheets for titania pigmented epoxy coatings

Utilization of Ti 3 C 2 nanosheets for enhancing anticorrosion of epoxy resin coatings has been reported. But the epoxy coatings in real world are mainly pigmented coatings. Unfortunately, the anticorrosion behavior of Ti 3 C 2 nanosheets for the pigmented epoxy coatings is rarely concerned. In this work, both 0.5 wt% unmodified Ti 3 C 2 nanosheets (U-Ti 3 C 2 ) or 0.5 wt% (3-glycidyloxypropyl)trimethoxysilane-modified Ti 3 C 2 nanosheets (G-Ti 3 C 2 ) were introduced into solvent-based titania pigmented epoxy coatings. Corrosion resistance of coatings was evaluated by electrochemical impedance spectroscopy and salt spray tests. A titania concentration effect was interestingly exhibited for the anticorrosion behavior Ti 3 C 2 -containing pigmented coatings. Enhanced anticorrosion was only demonstrated when TiO 2 content was not above 10 wt% for U-Ti 3 C 2 or 5 wt% for G-Ti 3 C 2 . Moreover, the pigmented coatings with U-Ti 3 C 2 have better corrosion resistance than those with G-Ti 3 C 2 , being contrary to the phenomenon observed in pure epoxy resin coatings. The different anticorrosion behavior of Ti 3 C 2 nanosheets for epoxy coatings with various TiO 2 contents was mainly attributed to the different dispersion states of TiO 2 pigments, that is, improved dispersion at low TiO 2 content and deteriorated dispersion at high TiO 2 content, after addition of Ti 3 C 2 nanosheets.