一步法制备超疏水表面及其防覆冰性能研究

One-step Preparation and Anti-icing Performance of Superhydrophobic Surface

目的提高铜网表面的防除冰性能。方法以铜网为基底材料,用纳米胶带将铜网和聚四氟乙烯(PTFE)固定在一起,采用飞秒激光直写技术将PTFE纳米颗粒部分嵌入铜网,采用一步法制备了PTFE附着铜网的超疏水表面,并通过扫描电子显微镜和光学显微镜对其微结构进行形貌分析。结果在PTFE低表面能和粗糙度共同作用下,所制备的表面表现出优异的超疏水性能,水的接触角为152°,滚动角为4°。在此基础上探究了其微观结构对表面润湿性和防覆冰性能的影响。结果表明,PTFE附着铜网的超疏水表面能有效延长冷凝液滴结冰时间,与未垫PTFE的铜网相比,结冰时间延长1.2倍。在冷却过程中,液滴从Cassie状态向Wenzel状态转变,PTFE附着铜网的超疏水表面能维持将长时间的Cassie状态。并且结冰后依然能保持较低的黏附力,最小冰黏附力为2.55 kPa,相比普通的超疏水表面缩小了近2.5%。同时能够实现冷凝液滴的高效快速自去除,还显示出优异的自清洁性能。结论PTFE附着铜网的超疏水表面可有效延长结冰时间,降低冰黏附力,具有优异的冷凝自去除和自清洁性能,且在5.01V的电压下,铜网表面能够有效防止冰的形成。

Ice on the surface of industrial equipment and building materials has brought many troubles to the normal production and life of people,such as wind turbine blades freeze,electrical wiring freeze and airplane wing freeze.The traditional active deicing strategies,such as mechanical deicing,photothermal deicing and chemical deicing,have a series of problems such as high energy consumption and easy environmental pollution.A large number of studies have shown that the superhydrophobic surface can reduce the contact area between materials and water droplets,so that water droplets are not easy to gather on the surface,and have the characteristics of extending the icing time and reducing the ice adhesion.However,the existing research has some problems such as cumbersome preparation process and unfriendly environment.The work aims to find a simple,efficient and green preparation method to improve the anti-deicing performance of the material surface.Copper mesh and polytetrafluoroethylene(PTFE)were fixed together with nano-tape,and PTFE nanoparticles were partially embedded on the surface of the copper mesh by femtosecond laser direct writing technology.The super hydrophobic surface of PTFE attached to copper mesh was prepared by one-step method.Different microstructures were processed on the PTFE surface by controlling femtosecond processing power,including xanthium(SC),flocculent(CL)and long columnar(SP)structures.The microstructures were analyzed by scanning electron microscope and optical microscope.Under the combined action of low surface energy of PTFE and roughness of copper mesh,the surface of PTFE attached copper mesh exhibited excellent superhydrophobic properties,and the contact angle of water reached 152°and the rolling angle was 4°.On this basis,the effects of microstructure on surface wettability and anti-icing properties were investigated.The results showed that the superhydrophobic surface of PTFE attached to copper mesh could not only reduce the contact area of the droplet,effectively prolong the freezing time of the droplet,but also greatly reduce the ice adhesion after freezing.The icing time was 1.2 times longer than that of unpadded PTFE copper mesh.During the cooling process,the droplets changed from Cassie state to Wenzel state,and the superhydrophobic surface of PTFE attached to the copper mesh could maintain the Cassie state for a long time to maintain the stability of the droplets.It still maintained a low adhesion after icing,and the minimum ice adhesion could be as small as 2.55 kPa,which was nearly 40 times smaller than the ordinary superhydrophobic surface.At the same time,it could realize efficient and rapid self-removal of condensate droplets,and also show excellent self-cleaning performance.The superhydrophobic surface of PTFE attached to copper mesh can effectively extend the icing time,reduce the ice adhesion force,and has excellent condensation self-removal and self-cleaning performance.The superhydrophobic surface of PTFE attached to copper mesh has an important application prospect in the field of anti-icing.This study provides a new idea and research method for anti-icing of overhead transmission lines,and is expected to promote the application of this method in the field of anti-icing.At a voltage of 5.01 V,the surface of the copper mesh can effectively prevent the formation of ice.