In this paper, a novel kind of hydrophobic waterborne polyurethane (PU) composite coating is introduced via a two-step process, i.e., the graphene oxide (GO) + carbon nanotubes (CNTs) hybrids as synergistical reinforcement, and nano-casting the surface with fresh lotus leave. The experimental results reveal that: 1) Comparing with pure PU coating, the composite coating showed enhanced mechanical properties due to effect of the GO + CNTs hybrid, i.e., tensile strength were increased from 19.28 to 26.77 MPa, hardness and maximum load were increased by 60% and 100% respectively. 2) The composite coating surface exhibited an increased contact angle from 70° to 121°, due to the nano/micro convex structure duplicated by lotus leaf. 3) The composite coating showed a great improvement of corrosion resistance, i.e., the inhibition efficiency could maintain 98.35% after immersing in 3.5% NaCl solution for 20 days. The present work provides a simple and environment-friendly process to prepare a hydrophobic composite PU coating without any organic solvents, toxic chemicals and surfactants, which is expected to be widely used in sever corrosion prevention areas, such as marine engineering and construction industry.

在本文中，通过两步法介绍了一种新型疏水水性聚氨酯（PU）复合涂层，即氧化石墨烯（GO）+碳纳米管（CNTs）杂化作为协同增强，纳米浇铸表面配鲜荷叶。实验结果表明：1）与纯PU涂层相比，由于GO+CNTs杂化的作用，复合涂层表现出增强的力学性能，即拉伸强度从19.28增加到26.77 MPa，硬度和最大载荷增加了分别为 60% 和 100%。2）由于荷叶复制的纳米/微凸结构，复合涂层表面的接触角从70°增加到121°。3）复合涂层的耐腐蚀性能有很大的提高，即，在3.5%的NaCl溶液中浸泡20天后，抑制效率可保持在98.35%。本工作提供了一种简单、环保的制备疏水复合聚氨酯涂层的方法，不含任何有机溶剂、有毒化学品和表面活性剂，有望广泛应用于海洋工程和建筑行业等严苛的防腐领域。