Preparation Of Silane-modified Nanofiller/bisphenol A Epoxy Resin Coatings And Study On Their Anti-corrosion Performance

Epoxy resin coating is one of the most widely used anti-corrosion coatings in the world.Nano-materials have been available to the field of modified anti-corrosion coatings owing to their excellent mechanical properties and anti-corrosion performance.Nevertheless,nano-materials have large surface energy and are easily agglomerated in the coatings,which intensely impedes their application range.In this paper,a functionalized silane coupling agent was synthesized to modify the surface of nanosilica and graphene oxide.The modified and unmodified nano-materials were added into epoxy resin to prepare epoxy resin composite coatings.The mechanical properties and anti-corrosion performance of composite coatings were investigated.The main research contents are as follows:1.2-?3,4-Epoxycyclohexyl?ethyltriethoxysilane?ETEO?was synthesized by hydrosilylation reaction using 1,2-Epoxy-4-vinylcyclohexane and triethoxysilane as substrate and its structure was characterized.The results revealed that when the catalyst dosage was 30 ppm,the reaction temperature was 65°C,and the reaction time was 6 h,the ETEO yield reached as high as 85.4%.2.The surface of nanosilica was modified with ETEO to obtain modified nanosilica?ETEO-SiO₂?,then the ETEO-SiO₂/epoxy resin coatings were prepared.ETEO-SiO₂ improved the mechanical properties of the coatings,conferring a better hydrophobicity.The impact strength of the coatings increased about 366%when the amount of ETEO-SiO₂ was 4 wt.%.The electrochemical measurements and salt spray test showed that the ETEO-SiO₂ significantly improved the anti-corrosion performance of the coatings.After immersion for 1500 h,the corrosion resistance of the coating with the addition of 4 wt.%ETEO-SiO₂ was still higher than 2×10¹⁰??cm².3.Graphene oxide was obtained using Hummers method,then was modified by ETEO to prepare modified graphene oxide?ETEO-GO?,and added to epoxy resin to prepare the composite coatings.Compared to graphene oxide,ETEO-GO was fluffy and had a larger lamellar spacing.ETEO-GO and graphene oxide could significantly reduce the local stress concentration and improved the impact resistance and hardness of the composite coatings.When the amount of ETEO-GO was 0.7 wt.%,the impact strength and the hardness of the composite coatings increased over 400%and 2 times,respectively.What's more,the excellent dispersion of ETEO-GO in epoxy resin could improve the corrosion resistance of the composite coatings.When the amount of ETEO-GO was 0.7 wt.%,the composite coating had the best anti-corrosion performance.