Light-Responsive Polyblend Films with Reconfigurable Surface Micropatterns as Rewritable Information Storage Media

Stimulus-sensitive surfaces with tunable morphologies exhibit a wide range of applications in the fields of surface science and engineering. Herein, a cost-effective yet practical strategy is proposed to fabricate photo-sensitive patterning surface on film/substrate wrinkle system based on an azo-containing polyblend. By manipulating the stress field of the bilayer system globally and/or locally upon the stress relaxation triggered by the reversible cis-trans isomerization of the azobenzene, heating/cooling triggered surface wrinkles on the polyblend films could be tailor-made with visible-light-irradiation. Notably, upon selective photo-irradiation, bespoke surface patterns may be cyclically generated or eliminated, allowing these reconfigurable patterned polyblend surfaces to be used as rewritable information storage media for non-ink printing. The as-prepared photo-printed information patterns with high-resolution are shown to be rewritable for multiple cycles and legible for over 90 d in dark ambient conditions. This study not only provides a versatile strategy for flourishing the stimulus-sensitive systems, but also sheds light on the stress relaxation-triggered morphological evolution of the wrinkling polyblend films.