Patterning dewetting in thin polymer films by spatially directed photocrosslinking

► Crosslinks can be spatially delivered to polymer films containing a photoactive bifunctional benzophenone molecule that photo-crosslinks irradiated regions of the film. ► When annealed, uncrosslinked poly (styrene) (PS) preferentially localizes onto photo-crosslinked PS. ► The patterns are qualitatively affected by film thickness, areal dimensions of the uncrosslinked regions, irradiation and heating times.