Understanding and Exploiting the Transport Behavior of Polymers in Confined Geometries

Georgia Tech Research Corporation, Atlanta GA

Investigators

Abstract

Currently there are significant knowledge gaps in fundamentally understanding the thermodynamic and transport properties of polymers in confined geometries (e.g. ultra-thin films), and the dependence of these properties on film thickness and preparation conditions. Recent studies have shown that a wide variety of polymer film properties deviate from bulk behavior as the film thickness decreases below some critical thickness. Our recent measurements suggest that bulk diffusion of penetrants through polymer ultra-thin films decreases dramatically with decreasing film thickness while the proton conductivity of polymer films does not appear to decrease in a similar manner. The overarching goals of this work are to characterize the proton transport and diffusion behavior of polymers in confined geometries, elucidate the length scales and magnitudes of such behavior, and develop a self consistent and comprehensive fundamental understanding of the mechanisms that are responsible for the observed phenomena. The intellectual merits of the proposal can broadly be defined as: (1) characterizing the proton transport in polymer ultra-thin films, (2) developing a fundamental model to explain the physiochemical properties of polymer ultra-thin films, and (3) exploiting the observed behavior to produce enhanced capabilities for proton exchange membranes for fuel cells using existing materials and processes. The broader impacts of this activity include: (1) providing guidance on and opportunities for overcoming some of the roadblocks in microlithography to benefit the microelectronics industry, (2) providing a way to enhance polymer membrane performance for fuel cells, (3) educating undergraduate and graduate students in a manner that synergistically blends modeling and experiment, and (4) enhancing underrepresented and minority student education and improving secondary school science education.