9423702 Phillies Polymer solutions are being studied with light-scattering spectroscopy (which is a non-invasive technique for determining the movements of dissolved macromolecules performing Brownian motion), optical probe diffusion (in which light scattering is used to monitor the diffusion of probe particles through a polymer solution), and rheological instrumentation. Probes of different sizes, and scattering experiments at multiple angles, are used to examine the importance of length scale effects in polymer transport. Careful determinations of light scattering spectral lineshapes will allow comparison of phenomena seen in viscous polymer solutions with phenomena seen in simple solutions near glass transitions. Experiment, supplemented with analytic theory, computer simulations, and systematic literature review, will be applied in efforts to refine or refute the hydrodynamic scaling model and other treatments of polymer dynamics. %%% The objective of this research is to improve scientific understanding of polymer dynamics (e.g., viscosity, viscoelastic behavior, self-diffusion, rotational diffusion) in dilute and non-dilute solutions. The dynamics of polymer solutions are important in a wide variety of scientific, technical, and practical applications, from the purely scientific (diffusion of proteins and mRNAs within living cells) to the mundane (thickness of milkshakes). ***
