Reversible Surface Wettability Control of Fluorinated Polyimides Having Spiropyran Groups by Photo-irradiation

Abstract

The novel polyimides having trifluoromethyl groups were synthesized and the introduction of spiropyran groups on their side chain by Mitsunobu reaction were succeeded. The films of obtained polyimides on glass substrates were prepared and the surface wettability of these films were measured before and after UV/VIS light irradiation. As a result, the initial contact angles of the novel spiropyran-containing fluorinated polyimides improved by up to 40°. As expected, the contact angle decreased by UV light irradiation and recovered by VIS light irradiation. However, the change in contact angle was about 10°, which was the same values as the result previously reported.