When certain numbers of charged ions, dispersed in a salty solution, are connected together in a chain-like fashion, the system exhibits tantalizing properties with additional tuning of chemistry of reactions. Examples of use of these materials include super-absorbancy of water in diapers, targeted delivery of large macromolecules such as genes using synthetic platforms, guided transport of charged macromolecules through nano-fluidic devices, and high electronic conductivity of polyelectrolyte films formulated from water-based solutions. Despite the high importance of charged polymers in today's materials world, fundamental understanding is limited. The difficulty arises from several long-range forces acting on the molecules simultaneously so that each molecule feels the presence of almost every other molecule in the system. The Principal Investigator proposes to bring a combination of experiments on carefully chosen model systems, computer modeling, and advanced theoretical methods to address several interrelated transport properties of polyelectrolyte systems. The project offers societal impact in terms of fundamental scientific understanding of advanced materials of broad technological relevance and use. One of the major components of the proposed research is to train the next generation of scientific leaders in this area so as to meet the growing global challenges and societal needs.
Experiments and development of new theories are proposed for polyelectrolyte dynamics, polyelectrolyte gel dynamics, and electrical conduction in polyelectrolyte systems, by combining single molecule electrophoresis, light scattering, rheology, statistical mechanics, field theory, and several simulation techniques. Several polyelectrolyte transport phenomena will be studied. Specifically, the project addresses (a) translocation of synthetic branched polyelectrolytes, (b) polyelectrolyte gel dynamics and diffusion of polyelectrolytes in polyelectrolyte gels, and (c) electronic conduction in polyelectrolyte systems. This project is aimed at building a new separation technique for polyelectrolytes with different architectures, and discovering new conceptual models for polyelectrolyte transport and electron transport in polyelectrolyte systems. The results of this research will have impact in numerous applied areas such as super-water absorbent goods, separation science, molecular sieves for separation techniques, drug delivery platforms, organic photovoltaic devices, organic light-emitting diodes, radio frequency identification tags, and antistatic coatings. Training of graduate students in this research area is the primary educational component of the proposed activity.
