Polymers in Flow

 

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The conformational evolution of single polymer chains can be manipulated using flows and/or fields. Monomer sequence – even in block copolymers – has a profound effect on conformations in such out-of-equilibrium scenarios. We are developing simplified models that will elucidate underlying physical fundamentals that inform the design of polymer systems.

 

Polymer structure and morphology have a rich array of tunable behavior. Tools such as precise chemistry and physical intuition have guided the manipulation of these materials to new levels of complexity. Likewise, advances in kinetically-driven systems using flows and fields provide an orthogonal way to tune systems. We desire further advances in dictating the behavior of materials desired for applications such as molecular organic electronics, drug delivery vehicles, and patterned substrates; we seek to understand the conformational evolution of complex polymer systems to enable these technologies. Our research is investigating the possibility that judicious and minimal design of monomer sequence or architecture are coupled with driving fields and flows may enhance the ability to explore the conformational and structural aspects of polymeric systems. Furthermore, we are interested in the competition between intra- versus inter-molecular effects in out-of-equilibrium polymer dynamics and rheology. We are interested in the fundamental connection between polymer dynamics, both at the single-chain and multi-chain level, and their molecular structure and properties (sequence, charge-based properties, architecture) in order to design new materials with tunable out-of-equilibrium properties. New theoretical and conceptual understandings that specifically take into account polymer structure and chemistry will allow the manipulation of polymers via the interplay between macroscopic controls and molecular-level features.

 

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Architecture can play a key role in single polymer dynamics. Topological constraints and branches (for example) can affect the dynamical behavior of these systems. Collaboration with the Charles Schroeder group seeks to fundamentally understand these effects.

 

WebFig3We are interested in the dynamics and rheology of charged polymer systems. The structure and sequence of the charged polymer components will strongly affect the ability of the system to respond to an applied stress, such that polyelectrolytes are often used in any number of viscosity-modification applications.