Study On Preparation Of SiO₂/Epoxy Resin Coating By Sol-Gel Method

In this paper, in order to get nano-hybrid coating with excellent performance, the coating is prepared through sol-gel process using TEOS as precursor, and bi-osphenol-A epoxy resin as the matrix.Techniques of the preparing coating and the performance of the coating including mechanics properties, anticorrosion performance and anti-ultraviolet performance is discussed in details.The preparation process is optimized through experiments, and the effect of catalyzer, silane coupling agent dosage and curing agent dosage on the coating are stressed; Then coatings with different formula are prepared according the optimized process, and performance of the coatings are investigated.Results indicate that when the dosage of HCl as catalyzer is 10% of TEOS in weight, the curing agent content is 40% of the epoxy resin in weight, the coating exhibits good performance. When the dissolvent is made of acetone, butyl alcohol and xylene, and shares 20% of the epoxy resin, it can guarantee the sol-gel process smoothly and good usability .Results indicate that the silane coupling agent plays an important role in the coating, and that when its content is between 15%-20% of the TEOS, the performance is best.Through IR and SEM, it proves that the silica in the coating disperses well, and the diameter is about 100 nm.Results indicate that the coating made by the sol-gel process exhibits excellent hardness, adhesion, impact stress and wear resistance and the most suitable content of SiO₂ in the epoxy resin is 12%.Results also indicate SiO₂/epoxy resin coating prepared by sol-gel process get good anti-ultraviolet performance.Methods of lost weight, polarization curve and electrochemical impedance spectroscopy indicates that the anti-corrosion performance of SiO₂/epoxy resin coating is improved distinctly, and the mechanism of the anti-corrosion is provided.