(152ax) Controlling Polymer Functionality and Dynamics in Plasticized Gas Separation Membranes Using Click Chemistry

Polymer membranes have been hailed as a promising technology for energy-efficient CO₂ and hydrocarbon separations due to their small form factors, low material costs, and inherent energy efficiency. However, conventional polymer membranes suffer from an inherent trade-off between permeability and selectivity according to the so-called Robeson upper bound. Additionally, membrane materials frequently exhibit performance degradation when separating industrial gas mixtures, particularly in the presence of plasticizing water and hydrocarbon vapors. Despite the ubiquitous challenge of plasticization, it remains challenging to predict the field performance of new membrane materials due to a poor quantitative understanding of the interrelationships between plasticization, free volume, and chain mobility.

As part of a new research group at the University of Florida, my work aims to understand the molecular principles that govern plasticization in gas and vapor separation membranes by leveraging molecular-scale synthetic control over both polymer structure and dynamics. Polymer post-functionalization strategies that rely on “click” chemistry offer routes to prepare well-controlled, molecularly-tunable polymer membranes. We aim to experimentally characterize how specific polymer dynamic modes and chemical functionalities control gas sorption and diffusion in polymer membranes using dielectric spectroscopy in tandem with gas transport measurements. To evaluate membrane performance, we will measure variable-pressure permeation and sorption of CO₂ and hydrocarbon gases (e.g., methane, ethane, and ethylene) in model polymer membranes to evaluate plasticization resistance and separation performance in the presence of both single gases and gas mixtures. These measurements will include gas mixtures containing humidity or organic solvent vapors to simulate industrially-relevant conditions. The ultimate goal of this research is to develop molecular principles to guide development of plasticization-resistant membranes that can efficiently capture CO₂ or separate mixtures of chemically similar hydrocarbons to address the growing issue of climate change and contributing to sustainable energy production.