(393m) Self-Assembly of Nanorods in Photosensitive Binary Mixture

Computer simulations reveal how photo-induced chemical reactions in polymeric mixtures can be exploited to create long-range order in materials whose features range from the sub-micron to the nanoscale. The process is initiated by shining a spatially uniform light on a photosensitive AB binary blend, which thereby undergoes both a reversible chemical reaction and phase separation. When a well-collimated, higher intensity light is rastered over the sample, the system forms defect-free, spatially periodic lamella structures. We now build on this approach by introducing nanorods that have a preferential affinity for one phases in a binary mixture. The rods form percolating network in the uniform light source. By introducing a secondary light with higher intensity and rastering over the sample with the proper velocity, we can create ordered arrays of rods within periodically ordered materials in essentially one processing step. Our method has the advantage to control lamella width and ordering of rods dynamically and can be applied to design complex hierarchically ordered structures.