Single molecule studies of flexible polymer systems

Polymeric materials play a profound role in our daily lives. There have been many key advances in polymer processing over the last several decades, but much of the underlying molecular behavior and physics of polymer solutions is not fully understood. Single molecule studies of polymer solutions provide an avenue for studying polymer dynamics and can aid in developing new molecular models of dynamic behavior. For nearly two decades, fluorescentlylabeled double stranded DNA (dsDNA) has been the model system for studying single molecule polymer dynamics in non-equilibrium conditions; however, dsDNA is a semiflexible polymer with markedly different local molecular properties compared to flexible polymer chains, such as synthetic organic polymers. This thesis presents a new methodology for studying truly flexible polymers at the single molecule level. We have demonstrated the ability to synthesize long strands of fluorescentlylabeled ssDNA, and we directly imaged single ssDNA polymers stretching in fluid flows in microfluidic devices (Chapter 2). In addition, we have developed an automated flow-based method to isolate individual polymer chains for long periods of time in planar extensional flow (Chapter 3). By combining the tools we developed we were able to study the longest polymer relaxation time dynamics of flexible polymers (Chapter 4), and utilizing both Brownian dynamics simulations and single molecule experiments, we were able to study the relaxation dynamics of flexible chains. In addition, we were able to use to automated hydrodynamic trap to study dynamics of polymers in precisely controlled flow conditions that have not been studied previously (Chapter 6), as well as the dynamics of a different class of materials: ring polymers.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Brockman, Christopher A.

Contributors dc:contributor

• Schroeder, Charles M.
• Higdon, Jonathan J.L.
• Kenis, Paul J.A.
• Ewoldt, Randy H.

• Fluorescence microscopy
• polymers
• single molecule dynamics

Statement dc:rights

• Copyright 2014 Christopher Brockman

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/49461

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/49461