(237e) Shear Alignment of Neat and Nanoparticle Loaded Block Copolymer Hydrogels

Self-assembled block copolymer templates are used to control the nanoscale structure of materials that would not otherwise order in solution. In this work, we have developed a technique to use close-packed cubic mesophases of a thermoreversible block copolymer (PEO-PPO-PEO) to impart spatial order on dispersed nanoparticles. The soft block copolymer template is easily aligned to a near single crystal using simple shear. SANS experiments demonstrate that shear can be used to probe the alignment into single-crystal macro-domains. We are currently utilizing SANS to understand the flow mechanisms of several types of these block copolymer micelle crystals and co-crystals. The nature of the shear field, history and details of crystal packing are all important in the mechanics of the gels. The impact of crystal structure and dispersed particle properties on shear alignment and flow properties will be presented.