为探寻用于疏水表面制备的仿生原型,测试了东亚飞蝗(Locusta migratoria manilensis)体表典型部位的润湿性.采用扫描电子显微镜和三维形貌干涉仪对体表微形貌结构进行了观测,基于Wenzel模型和Cassie-Baxter模型简要分析了体表典型部位的疏水机理.结果表明,体表不同部位的润湿性呈现差异,其中水滴在内翅表面的接触角相对较大(132.92±4.73)°,在外翅表面的接触角相对较小(119.47±4.32)°,在颈部和口器表面的接触角介于两者之间.外翅表面分布着～100 μm级脊状凸起和纳米级蜡质膜层,内翅表面覆盖着毫米-微米级脊状凸起和大量微米-纳米级乳突,颈部和口器表面呈现凹凸起伏的毫米-微米级形貌结构,小区域的颈部和口器表面展现出相当光滑的微形貌.内翅因具有由脊状凸起和乳突构成的复合尺度结构而能使水滴产生Cassie-Baxter接触状态,从而呈现相对较大的接触角;其他典型部位的表面微形貌结构使水滴产生Wenzel接触状态而呈现相对较小的接触角.研究结果不仅能够量化表征东亚飞蝗体表典型部位的润湿特性,还可为疏水表面结构的仿生制备提供参考.%To search a bionic prototype for simple fabrication of superhydrophobic surface,the wettability of water droplets on typical parts of body surface in locust Locusta migratoria manilensis is measured,and micromorphology of these typical parts are detailedly examined with a scanning electron microscope and a scanning white light interferometer.Based on Wenzel model and Cassie-Baxter model,the hydrophobic mechanism of these typical parts is analyzed briefly.Results present that the contact angles of water droplets on these typical parts change obviously,as exhibiting the greatest value of (132.92 ± 4.73)° on internal wings and the smallest value of (119.47 ± 4.32)° on external wings,whereas the neck surface and the mouthpart surface presenting rather similar contact angle values.SEM and SWLI observations show that the surface of external wings distributes ～100 μm scaled ridge-like convexes and nano scaled wax coverings,and the surface of internal wings consists of milli-micro scaled ridge-like convexes and numerous micro-nano scaled mastoids.Both the neck surface and mouthpart surface show undulate structures with milli-micro ranged parameters,whereas present rather smooth micromorphology when examining a rather small area.The surface of internal wings possesses the dual structures consisting of ridge-like convexes and numerous mastoids,thus it makes water droplet to generate the Cassie-Baxter contact state and consequently exhibit great contact angles.Other typical parts of the locust's body surface possess the microstructures to make water droplet to generate the Wenzel contact state and thereby exhibit relatively smaller contact angles.The obtained conclusion can quantitatively describe the wettability of typical parts in locust body surface,as well as provides a theoretical foundation for developing bioinspired materials with hydrophobic properties and self-cleaning abilities.
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