9807591 Thomas This proposal describes a research program aimed at developing novel macromolecular materials for technological applications. The first area is traditional: morphology and mechanical properties; and the second is completely new: block copolymer photonic band gap (PBG) materials. Both areas depend critically on the ability to organize block copolymers into well ordered microdomain morphologies using composition, molecular architecture, and careful processing. Tailored self assembly into new microdomain structures such as the double gyroid tricontinuous structure in ABA triblocks is exemplary for understanding how the microdomain structure of a glassy continuous (polystyrene end blocks) and a rubber continuous (polyisoprene mid block) system evolves with increasing deformation and substantially recovers upon release of the applied load. The continued exploration of ABC terpolymers, both linear and miktoarm stars, will undoubtedly reveal additional new microdomain structures. The object is to gain an overall understanding of how composition, number of components and chain architecture govern the resultant structure of the intermaterial dividing surface of the periodic microdomains. In the second area, a new field will be explored, of potentially huge significance for block copolymer materials and their interesting topologically connected microdomains by using them in combination with high dielectric contrast nanoparticles to create novel photonic band gap materials. PBG materials are a new class of materials with enormous potential to revolutionize electroptical and all optical applications. Up to the present, this new field has been pioneered using microlithography to pattern periodic dielectric structures. By sequestering nanoparticles into one of the components of an appropriately high Mw block copolymer, structures with excellent dielectric contrast and appropriate length scale can b produced to control the flow of U.V. and visible li ght. %%% These two projects are in the areas of polymer-based structures for technological applications. In addition to the basic science and new technology, both graduate students and undergraduate students will be exposed to multidisciplinary training in these exciting project thrust areas. ***
