Rewritable Spiropyran/Polyacrylonitrile Hybrid Nanofiber Membrane Prepared by Electrospinning

摘要

Photochromic materials aroused enormous interest due to their potential application for rewritable paper, smart labeling and sensor devices. In this paper, we proposed to dissolve spiropyran (SP, photochromic material) and polyacrylonitrile (PAN, polymer matrix) in dimethyl fumarate (DMF) to prepare photochromic nanofibers by electrospinning. The target SP compounds were featured by FTIR, ultraviolet (UV) and (HNMR)-H-1, and the nanofibers were characterized by FTIR, UV-vis spectra, scanning electron microscope (SEM), thermal gravimetric analysis (TGA) and contact angle (CA). The test results demonstrated that photochromic SP was synthesized successfully, and the nanofiber membrane possesses extraordinary color-converting properties including obvious color change from white to purple, reversible fast switching between two colors when exposed to UV light and achieve maximum color change in 1 min, and switchable hydrophilic and hydrophobic properties as well as excellent photo-fatigue resistance over 20 cycles. In addition, it has good thermal stability allowing it to be used under harsh conditions. In view of the above characteristics, we believe that the as-prepared nanofiber film will be a promising reusable writing substrate.