Soft materials exhibit an array of structures that reflect the optimization of complex and delicate molecular interactions. At length scales between ~ 1 nm and ~1 μm, interfacial curvature and packing geometry reflect the self-assembly of molecules with prescribed architectures. One class of soft material, block copolymers, provides the opportunity to design materials with attractive chemical and mechanical properties based on their ability to assemble into periodic structures with nanoscale domain spacings. In addition, modern polymerization methods afford access to an array of block copolymer architectures, ranging from two-monomer diblocks to branched configurations that may incorporate almost any number of different polymers.
The primary focus of the Epps laboratory lies in designing, building, and characterizing new polymeric materials exhibiting molecular level self-assembly. Several applications for block copolymers and polymer blends under investigation in our group include: battery and fuel cell membranes, organic photovoltaics, analytical separations membranes, nanoscale containers and scaffolds for targeted drug delivery, precursors to electronic arrays, and surface responsive materials. We manipulate polymer internal and external interfacial characteristics in bulk and thin film environments to influence the ordering and stability of polymer structures. Assembly processes in our materials are explored with a comprehensive array of reciprocal space (small and wide-angle x-ray and neutron scattering), real space (optical, scanning probe, and electron microscopy), mechanical (dynamic mechanical analysis), and spectroscopic (x-ray photoelectron spectroscopy, near-edge x-ray absorption fine structure, and infrared spectroscopy) techniques. Researchers in the group gain experience in chemistry, chemical engineering, materials science, and biology. Our work can be divided into the following areas:
Nanoporous Block Copolymer Templates for Biological and Chemical Separations
Combinatorial Methods in Surface Responsive Polymer Films
Block Copolymers in Solution