Dynamics of polyelectrolyte solutions and diblock copolymer in an electric field
We present a theoretical treatment of the dynamic properties of polymer and polyelectrolyte solutions, incorporating the screening associated with hydrodynamic, excluded-volume and electrostatic interactions. The importance of inter-chain interactions in influencing properties like the viscosity of a polyelectrolyte solution is emphasized. This treatment is then extended to cover the case of living polymers, specifically, the rheological properties of wormlike micelles. We also investigate the effect of simple shear and elongational flows on the configurational and rheological properties of a single polymer chain. The coil-stretch transition of a polymer under elongational flow was investigated, results indicating a possible first order transition. We also study the behavior of confined diblock copolymers in lamellar and cylindrical morphologies when placed in an external electric field. The crucial parameter influencing the value of the critical electric field above which the diblock orients itself parallel to the field, is found to be the mismatch in the interfacial tensions between polymer and plate, with a mismatch in dielectric constants of the copolymer components also playing a role.