Event
Physical Chemistry Seminar: Dr. Jennifer Laaser
Title "Chemical Determinants of the Phase Behavior and Viscoelasticity of Polyelectrolyte Complex Coacervates"
Dr. Jennifer Laaser
University of Pittsburgh
-Complex coacervates are a class of polymeric materials formed by associative phase separation of charged polymers in aqueous solution. While the environmental factors that determine the phase behavior and physical properties of these materials, such as temperature and salt concentration, are well-understood, far less is known about how specific chemical interactions between the polymers impact these properties. To address this problem, we use post-polymerization functionalization to prepare polymer libraries with varied charge density, hydrophobicity, and aromaticity, and characterize the phase behavior and thermodynamics of complexation of the resulting materials. We show that hydrophobic interactions matter primarily when the hydrophobic units contain carbon chains of length 6 or more, and that cation-pi interactions substantially stabilize complexes of aromatic polyelectrolytes. This work brings new insights into the chemical interactions underlying the properties of polyelectrolyte complexes and coacervates and promises to inform development of materials with targeted properties under specific solution conditions.
Prof. Laaser is a physical chemist with a strong interest in polymer physics and polymeric materials.
She received her Ph.D in 2013 from the University of Wisconsin-Madison, where she worked with Martin Zanni to develop new methods in ultrafast spectroscopy for investigating the structure and dynamics of molecules at interfaces. After leaving UW-Madison, she was a postdoctoral associate at the University of Minnesota, where she worked with Timothy Lodge to develop a detailed understanding of micelle-based polyelectrolyte complexes for gene delivery applications.
She joined the faculty at the University of Pittsburgh in August 2016, where she now runs a research group straddling the boundary between physical chemistry, polymer physics, and polymeric materials.
Outside of her research, Prof. Laaser has a strong interest in science outreach, and can often be found explaining cool science to anyone who will listen.
https://laaserlab.chem.pitt.edu/team_member/jennifer-laaser/
HOST: Fakhraai