采用环境扫描电子显微镜(ESEM)观测了蝴蝶翅膀的微观结构,揭示了蝴蝶翅膀颜色的各向异性特征.采用高速摄像仪实时动态观察了蝴蝶翅膀的水凝结浸润特性,分别探究了蝴蝶翅膀在水平、不同倾斜角度以及在振动条件下的水凝结的憎水性.基于微观结构,对蝴蝶翅膀的水凝结憎水特性进行机理阐述.定量描述了其表面的黏滞特性,并基于蝴蝶翅膀的微观结构效应阐述了翅膀表面水凝结的憎水性机制.
We use the environmental scanning electronic microscopy(ESEM) to observe the micro-/nanostructure of Morpho nestira butterfly wing,and reveal the anisotropic structure feature in conjunction with iridescent structural color of butterfly wing.We observe the dynamic characteristics of water condensation and wettability on butterfly wing by the high-speed camera,and discuss the water repellency on butterfly wing under different tilt-degree and vibration conditions.It is found that a robust water repellency property appears on Morpho nestira butterfly wing.The dynamic contact angle experiment is used to examine the contact angle hysteresis by measuring the advancing angle and receding angle,the low adhesion property in conjunction with contact angle hysteresis can be demonstrated by the difference of receding angle and receding angle.The result reveals that the robust water repellency on Morpho nestira butterfly wing is attributed to the effect of micro-and nano-structure on butterfly wing.Furthermore,we elucidate the mechanism of special wettability and repellency of water condensation based on micro-/nano-structures of butterfly wing.