Novel photoresponsive N-hydroxyethyl spiropyran (SP-OH)/polyacrylonitrile (PAN) fiber materials with reversible changes in wettability and humidity were prepared by electrospinning in this work. SP-OH and PAN were mixed through a physical doping method. The wettability and humidity regulation of the electrospun films can be reversibly manipulated by the simple change of ultraviolet (UV)-visible (UV-Vis) light irradiation due to the photoisomerization mechanism of the spiropyran chromophore. Under UV light irradiation, SP-OH molecules exhibit a colored polar open-ring status, resulting in electrostatic attraction with water. However, under visible light irradiation, they are colorless and nonpolar and lose the attraction effect. Wettability and ambient humidity were regulated by this repeated transformation between polar surface and nonpolar surface. The tensile strength and the reversible change ranges of wettability and humidity under UV-Vis irradiation are all closely related to the doping amount of SP-OH. Electrospinning is a promising method to achieve large-scale production that can put such a material into practical application.

中文翻译：

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静电纺丝自动调节润湿性和湿度制备具有机械稳定性的可逆光响应N-羟乙基螺吡喃/聚丙烯腈纤维材料

在这项工作中，通过静电纺丝制备了具有可逆性润湿性和湿度变化的新型光响应 N-羟乙基螺吡喃 (SP-OH)/聚丙烯腈 (PAN) 纤维材料。SP-OH和PAN通过物理掺杂方法混合。由于螺吡喃发色团的光异构化机制，电纺薄膜的润湿性和湿度调节可以通过紫外（UV）-可见光（UV-Vis）光照射的简单变化来可逆地控制。在紫外光照射下，SP-OH分子呈现有色极性开环状态，与水产生静电吸引。但在可见光照射下，它们是无色无极性的，失去吸引力。通过极性表面和非极性表面之间的这种重复转换来调节润湿性和环境湿度。UV-Vis照射下的拉伸强度和润湿性和湿度的可逆变化范围都与SP-OH的掺杂量密切相关。静电纺丝是实现大规模生产的一种很有前途的方法，可以将这种材料投入实际应用。