具有自修复功能的超疏水防腐涂层性能研究

Study on the Performance of Superhydrophobic Anti-corrosionCoating with Shape Memory Effect

为克服海洋环境有机涂层耐久性差等缺陷,制备了具有长效疏水性能兼具自修复功能的复合涂层。首先在金属基体表面涂覆环氧基形状记忆聚合物(SMP),再与聚己内酯(PCL)纳米纤维膜结合获得具有自修复功能的复合膜,然后通过气压喷涂将十八烷基三甲氧基硅烷改性的硅藻土颗粒结合在复合膜表面,待其固化后得到具有自修复功能的超疏水防腐涂层。采用扫描电子显微镜(SEM)观察涂层表面的微观形貌,并使用接触角测量仪测试涂层表面的超疏水性;采用激光共聚焦显微镜(CLSM)测试涂层表面的粗糙度并表征涂层的自修复性能;通过砂纸磨损、电化学阻抗谱(EIS)评价涂层的耐磨性和防腐性能。结果表明:成功制备了具有自修复功能的超疏水复合涂层。该涂层在50℃下加热2 h,表面裂纹即可明显修复;完整的超疏水防腐涂层在3.5%NaCl溶液中浸泡21 d后,其阻抗模值依旧保持在1011Ω∙cm^(2),比纯树脂涂层提高了5个数量级,浸泡63 d后,阻抗模值依旧保持在1010Ω∙cm^(2),经过12次破坏-修复循环后,超疏水防腐涂层的阻抗模值仍保持在1010Ω∙cm^(2)。另外,该涂层还具有优异的耐磨性,在100 g荷载、600目砂纸磨损测试2000 cm(40个循环)后,涂层的水接触角(WCA)依旧可以保持在150.2°。纳米纤维复合膜赋予涂层自修复功能,硅烷改性的硅藻土赋予涂层超疏水特性,二者结合形成的复合涂层具有优良的疏水性、耐磨性和防腐性。本研究将为海洋等严苛环境超耐久涂层的选择提供依据。

Superhydrophobic coating had attracted much attention due to their unique self-cleaning,anti-pollution,anti-icing,and anti-corrosion properties.However,the poor durability,single functionality,and easily damaged structure of most superhydrophobic coating seriously hindered their practical application in marine environments.To address this challenge,integrating self-healing functionality into superhydrophobic coating to repair damaged surface chemistry and morphology was an effective strategy for extending coating life.However,research on superhydrophobic coating with self-healing function was still limited under actual environmental conditions.Shape memory polymers(SMP)provided a new approach to address this issue.In this paper,a superhydrophobic coating with self-healing function was fabricated,which relied on the dual action of epoxy SMP and PCL nanofibers to restore both its physical and chemical properties.The PCL nanofiber membrane supported the superhydrophobic particles in the top layer and was connected to the organic resin in the below layer.The obtained coating showed outstanding barrier properties and the corresponding impedance modulus was maintained about 1010Ω∙cm^(2)after 63 immersion days.Notably,the impedance modulus of the coating remained at 1010Ω∙cm^(2)after 12 damage/healing cycles.Moreover,the coating surface had retained superhydrophobicity after abrasion test with 600-grit sandpaper under a load of 1000 g for 20 m distance.This research will provide a basis for selecting ultra-durable coatings in marine environments and offer a reference for the application of superhydrophobic coatings in metal corrosion protection.