Wetting Transition in Cylindrical Alumina Nanopores with Polymer Melts

We report a systematic study of the wetting of cylindrical alumina nanopores with polystyrene melts. A transition from partial to complete wetting was observed with increasing annealing temperature, resulting in the formation of very different one-dimensional polymeric nanostructures (nanorods and nanotubes) within cylindrical alumina nanopores. The wetting transition temperature is dependent on the polymer molecular weight. The large difference in the wetting rate between partial and complete wetting was successfully used to fractionate polymers with different molecular weights.