Shape memory surface adhesion control based on PU-CNC/PS electrospun composite films

Abstract

Wettability is a fundamental property of solid surfaces. The adhesion of liquids to solid surfaces, especially the intelligent control of surface adhesion, plays an important role in the wettability field, showing broad prospects in self-cleaning, anti-icing, oil–water separation and chemical reactions, etc. In this work, a new shape memory composite film was prepared by electrospinning, consisting of water-responsive shape memory substrate of polyurethane-cellulose nanocrystalline composite fibers and a superhydrophobic polystyrene spindle-fiber surface. Benefiting from the water-responsive shape memory performance of polyurethane-cellulose nanocrystalline substrate, the polystyrene surface spindle-fiber microstructures show sparse-dense switching during the stretching-recovery shape memory cycle, giving rise to smart control of surface adhesive behavior in superhydrophobic high-low adhesion. Given the flexibility and versatility, we demonstrate applications of the shape memory composite film in lossless droplet transfer, selective manipulation of multiple droplets, and smart detection. The composite film would provide potential applications in intelligent platforms, microliquid systems, and wearable fields, etc.