Tunable hydrophobicity assisted by light-responsive surface micro-structures

In this work we investigate new degrees of freedom in controlling the physical properties of structured photo-sensitive materials that can be usefully exploited in many application fields. We employ azopolymers, a class of light responsive materials, which are structured in micro-pillar array. A reversible and controlled change in morphology of a prepatterned polymeric film under properly polarized illumination is demonstrated to provide the opportunity to engineer surface structures and dynamically tune their properties. We exploit the laser process taking advantage of the lightinduced deformation of a micro-textured azopolymeric film in order to modify the surface hydrophobicity along specific direction.