Competition Between Effects of Pore Sizes and Annealing Solvents on the Morphology Manipulation of 3D Block Copolymer Nanostructures Using Anodic Aluminum Oxide Templates

In this work, the morphologies of polystyrene-block-polydimethylsiloxane (PS-b-PDMS) nanostructures using solvent-induced wetting in the nanopores of anodic aluminum oxide (AAO) templates are investigated. AAO templates with three different pore sizes (≈200, ≈60, and ≈30 nm) are used in this work to differentiate the effect of confinement and annealing solvents. Different from the results by the traditional wetting methods, two major effects are identified in affecting the morphologies. At larger pore sizes, the morphologies of the nanostructures are mainly affected by the annealing solvent. At smaller pore sizes, however, the morphologies are mainly controlled by the confinement effect (pore sizes). (Figure presented.) .