在強化金屬防腐蝕的研究中，我們發展電化學剝離法的石墨烯奈米複合材料作為保護層，選用聚胺脂或環氧樹脂與電化學剝離石墨烯來合成複合材料。電化學剝離法的石墨烯製造過程容易、生產成本低、並且對環境無害，因此我們選用此種製程的石墨烯來合成複合材料。在這項研究中，探討了石墨烯片層的大小對防蝕的影響，利用小型超音波細胞砸碎機來製備兩種大小不同的電化學剝離石墨烯片層，其平均面積為(大:13.35 µm2 , 小: 2.87 µm2)，並改變電化學剝離石墨烯的濃度去作探討，研究方法是將複合材料浸泡在氯化鈉溶液中利用電化學量測。結果發現，電化學剝離法所得石墨烯皆有良好的分散性，不論是在聚胺脂或是環氧樹脂的溶液中，並且可以穩定的附著在如銅或鋼鐵之金屬表面。此外，所有複合塗層皆可以增強金屬的抗蝕的能力，尤其是大片層的電化學剝離石墨烯塗層的防蝕能力更好，含0.5 wt% 大片層電化學剝離石墨烯複合聚胺脂之塗層浸泡在0.1M 的氯化鈉溶液中，可得到最低的腐蝕速率 4.0×10-4 mm/year ，比純的聚胺脂塗層腐蝕速率2.7×10-3 mm/year的效果還要好。而含0.75 wt% 大片層電化學剝離石墨烯複合環氧樹脂塗層具有最佳的防蝕能力2.3×10-5 mm/year。在應用上，若結合此兩種複合塗層，一層堆疊一層的方式可加強其防蝕能力，尤其在基底層和第二層利用環氧樹脂與電化學剝離石墨烯塗層，最外層用聚胺脂與電化學剝離石墨烯塗層的複合方式，在3.5 wt%的氯化鈉溶液中，可得到最佳的防蝕速率1.81×10-5mm/year。;Nanocomposite coatings with electrochemical exfoliating graphene as a filler are developed to enhance the corrosion protection on metal substrates. Polyurethane and epoxy were used in this study. Using simple method to produce electrochemical exfoliating graphene (EC-Graphene) into polymer matrix. EC-Graphene was used because it has a low production cost, easy to produce and environmentally friendly. Large and small flake size graphene were explored to improve the corrosion resistance of composites. EC-Graphene flakes of two different average sizes (large: 13.35 µm2 and small: 2.87µm2) were prepared by a probe tip sonicator. The composites were prepared with varying content of graphene and the electrochemical measurement was conducted in sodium chloride solution. The results show that EC-Graphene has a good dispersion either in polyurethane or epoxy matrix. And also it can be coated on the metal surfaces such as copper and carbon steel. All filler could enhance the corrosion resistance of the composites. Hence we found that EC-Graphene with a large flakes size superior to EC-Graphene with a small flakes size. In low concentration of sodium chloride (0.1 M), adding 0.5 wt% large EC-Graphene into polyurethane can lower the corrosion rate to 4.0×10-4mm/year which is much better than the pure polyurethane. While for epoxy, the lowest corrosion rate was achieved within adding 0.75 wt% of large graphene with the value 2.3×10-5 mm/year. For the application of coating system, we also tested stacking Epoxy/Polyurethane/ EC-Graphene composite coatings in 3.5 wt% NaCl. Coating used layer by layer system with Epoxy/ EC-Graphene as base coat or primer coat and Polyurethane/ EC-Graphene as outer coat coated on carbon steel. We could obtain the corrosion value up to 1.81×10-5 mm/year. Furthermore, the facile and ecofriendly method would be promising process fabricating graphene-based nanocomposites and develop their application in the anticorrosion field.
