The overall focus of this research is to apply scattering techniques to examine the phase behavior and kinetics of order-disorder and order-order phase transitions in multiblock copolymers in selective solvents using small angle neutron scattering (SANS), small angle x-ray scattering (SAXS), atomic force microscopy (AFM), and computer simulation methods. A major focus of this research will be to use synchrotron based time-resolved SAXS to follow the time evolution of structural features, and relate them to theoretical models of nucleation and growth kinetics of disorder-order transitions and of transitions between different ordered states. We will also initiate preliminary studies using AFM imaging to characterize the surface morphology of films of these micro-phase separated materials. The proposed research will provide detailed insight into the kinetics of the phase separation mechanisms involved in these different transitions, as well as in the mechanisms involved in the growth of micelles themselves.
An understanding of the phase behavior of multiblock copolymer solutions and gels is important to their numerous applications in materials science and technology. An exciting potential application is to use them as templates for nanolithography of solid state devices. The proposed AFM and SAXS studies of block copolymer films have direct relevance to the potential application of these films in nanolithography. The research will also lead to advances in designing and building specialized components for use at beam line facilities and data analysis programs with a wide range of applicability. The proposed studies will lead to the Ph. D dissertations of two graduate students (including one female American student) and provide research opportunities for undergraduates. The project also involves international collaboration with scientists in Czech Republic.
