Modification Effect Comparison Of Titanium Black And TiO₂ Nanoparticles On Epoxy Resin Coatings

Metal corrosion is closely related to both national economy and our daily life, and painting on metal surface is the most effective and widely used method among many protective measures. Today the application of nano-TiO2 in coatings has achieved remarkable progress, while the titanium black, a kind of low-valent titanium oxidation, has few reports on its application in anti-corrosion coatings. In order to obtain the modification rule of nano-sized titanium black in coatings and expand its application, epoxy resin was chosen as the film former substances, and different amounts of nano-sized titanium black or TiO2 were added respectively to compare their modification effect in coatings.First, X-ray diffraction (XRD), transmission electron microscope (TEM), and resistivity test were used to characterize the titanium black prepared by our group. The results show that it is a nano-sized mixture of TiO and Ti2O3(mass ratio is 1:3.3), and it has good electrical conductivity and crystallinity. Different amounts of titanium black or TiO2 were mixed with xylol and n-butyl alcohol, made ultrasonic dispersion, then mechanically mixed with epoxy resin to obtain coatings. After painting on steel plates, the impact, flexibility and adhesion tests were performed for mechanical properties measurement, then immersion tests in 10% H2SO4 solution,10% NaOH solution and seawater, salt spray test and electrochemical impedance spectroscopy (EIS) were used to measure their anti-corrosion performance.Mechanical property tests show that, when the mass content of nano-TiO2 in epoxy coating is 3%, the impact strength increased by 83%, flexibility increased 1 grade, adhesion strength increased by 10%. While the mass content of nano-sized titanium black in epoxy coating is 2%, the impact strength increased by 550%, flexibility increased 2 grades, adhesion strength increased by 116%. Anti-corrosion tests show that after modification, the corrosion resistance in alkaline solution is the best, in seawater is second, and in acid solution is the worst. And the addition of nano-TiO2 needs 3% in mass content while the nano-sized titanium black just needs 2%, and the more titanium black will decrease the corrosion resistance of modified coating.From this paper we know that the introduction of nanoparticles in epoxy resin coatings can improve both mechanical properties and corrosion resistance. And compare with nano-TiO2, fewer nano-sized titanium black can obtain a better effect, indicative of a good prospect of nano-sized titanium black applying in anti-corrosion coatings.