Preparation of Photoresponsive PAN-NH2@EPESP Fiber Films with Mechanical Stability for Regulating Wettability and Micro-environment Humidity

In view of the current living micro-environment and requirements of green economy, intelligent light-responsive humidification materials have become a hot spot in intelligent polymer materials. In this work, reversible photoresponsive films with a mechanical stability and an excellent humidity adjustment performance are developed by modifying epoxy-ether-spiropyran(EPESP) on amino-nanofibers(PAN-NH2), which was produced through electrospinning. Such smart films for regulating wettability and micro-environment humidity can be reversibly manipulated by the simple switch of UV and visible light irradiation because of the unique transformation between polar ring-opened status and nonpolar ring-closed status of the spiropyran units. The effects of EPESP modification amount on the morphology, wettability, tensile strength and the ability to regulate humidity were investigated in detail. The results show that with the increase of modification amount of EPESP, both the humidity regulation and tensile strength increased; when the modification amount exceeds 7 mg, the range of regulating humidity increases slowly.