Polymeric shape-memory micro-patterned surface for switching wettability with temperature

Abstract

An innovative method to switch the wettability of a micropatterned polymeric surface by thermally induced shape memory effect is presented. For this purpose, first polycyclooctene (PCO) is crosslinked with dicumyl peroxide (DCP) and its melting temperature, which corresponds with the switching transition temperature (Ttrans), is measured by Dynamic Mechanical Thermal Analysis (DMTA) in tension mode. Later, the shape memory behavior of the bulk material is analyzed under different experimental conditions employing a cyclic thermomechanical analysis (TMA). Finally, after creating shape memory micropillars by laser ablation of crosslinked thermo-active polycyclooctene (PCO), shape memory response and associated effect on water contact angle is analyzed. Thus, deformed micropillars cause lower contact angle on the surface from reduced roughness, but the original hydrophobicity is restored by thermally induced recovery of the original surface structure.