纳米石墨/聚氨酯复合涂层的制备及耐腐蚀性能

为研制高性能电力金具防护涂层，首先，以羟基丙烯酸树脂和异氰酸酯为主要成膜物质，纳米石墨为填料，制备了不同纳米石墨含量的纳米石墨/聚氨酯复合涂料；然后，将涂料喷涂在电力热镀锌钢上，固化干燥后得到纳米石墨/聚氨酯复合涂层；最后，测试了纳米石墨/聚氨酯复合涂层的力学性能和耐磨性，并采用模拟酸雨试验、中性盐雾试验及电化学阻抗谱（EIS）研究了纳米石墨/聚氨酯复合涂层的耐腐蚀性能。结果表明:添加纳米石墨后，涂层与热镀锌钢的附着力有所提高，纳米石墨含量为2.0wt%的纳米石墨/聚氨酯复合涂层的耐磨性比未添加纳米石墨的空白涂层提高了92%，并且涂层中纳米石墨的分布较均匀，表现出良好的耐腐蚀性能。 所得结论表明在涂层中添加适量的纳米石墨可以提高涂层的耐磨性和耐腐蚀性能，进而可将涂层用于电力金具的表面防护。 

Preparation and anti-corrosion performances of nano-graphite/polyurethane composite coatings

In order to investigate high performance protective coatings for electric power fittings, nano-graphite/polyurethane composite paintings with different nano-graphite contents were prepared firstly using hydroxyl acrylic resin and isocynate as main film-forming substances as well as nano-graphite as fillers. Then, the nano-graphite/polyurethane composite paintings were applied on electric hot dip galvanized steel, and nano-graphite/polyurethane composite coatings were obtained after solid drying. Finally, the mechanical properties and abrasion resistance of nano-graphite/polyurethane composite coatings were tested, and the anti-corrosion performances of nano-graphite/polyurethane composite coatings were investigated using simulated acid rain tests, neutral salt spray tests and electrochemical impedance spectroscopy (EIS). The results show that the adhesion between coating and hot dip galvanized steel is improved after adding nano-graphite, the abrasion resistance of nano-graphite/polyurethane composite coating whose nano-graphite content is 2.0wt% is improved by 92% comparing with the blank coating without adding nano-graphite, and the distribution of nano-graphite in the coating is relatively uniform, which shows good anti-corrosion performance. The conclusions obtained show that the addition of nano-graphite with suitable amount in coatings can enhance the abrasion resistance and anti-corrosion performances of coatings, thus the coatings can be used for surface protection of electric power fittings.