Nanoscale Dynamics of Polymer Thin Film Interfaces in Aqueous Solution
Abstract
It is critically important to correlate the nanoscale contributions of molecular morphology and interface chemistry to the chemical and mechanical stability of polymer thin films. The ability to measure these structure?property relationships can inform the design of new materials for applications including energy storage, membrane separations, and protective coatings where material performance is ultimately dictated by phenomena at the nanoscale. Membrane technologies represent a core component of the global water production portfolio and are currently plagued by premature failure due to fouling or chemical degradation of the membrane surface. In the work performed here, membrane relevant materials in contact with aqueous solutions are investigated using quartz crystal microbalance with dissipation (QCM-D) as a core characterization tool to deliver novel insights and rapidly assess alternative designs. The operational mechanisms of QCM-D enabled high precision (ng/cm2) mass transfer studies with millisecond time resolution to ascertain the polymer – solution interaction dynamics. Model systems have been developed to work within the limitations of the QCM-D measurement platform. A membrane cross-flow cell was used to corroborate the nanoscale characterization with macroscale performance parameters. With a deeper understanding of the fundamental molecular processes gained through advancements in nanometrological techniques, materials function can be better tailored to meet engineering challenges of the future. Strategies that aim to improve service lifetimes, reduce process energy input and complexity, toward more sustainable membrane separations are discussed.
Degree
Ph.D.
Advisors
Howarter, Purdue University.
Subject Area
Materials science
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