The development of a high-throughput/ combinatorial workflow for the study of porous polymer networks

Partha Majumdar¹, James Bahr¹, Elizabeth Crowley¹, Alekhya Kallam¹, Nathan Gubbins¹, Kris Schiele¹, Michael Weisz¹, Shawn M Dirk³, Joseph L Lenhart⁴, Bret J Chisholm^1,2
1Center for Nanoscale Science and Engineering, ²Department of Coatings and Polymeric Materials, North Dakota State University, Fargo, North Dakota, ³Sandia National Laboratories, Albuquerque, New Mexico, 4US Army Research Laboratory, Aberdeen, Maryland, USA

Abstract: A high-throughput workflow was developed for the study of porous polymers generated using the process of chemically induced phase separation. The workflow includes automated, parallel preparation of liquid blends containing reactive, polymer network-forming precursors and a poragen, as well as a high-throughput poragen extraction process using supercritical CO₂. A structure–process–property relationship study was conducted using epoxy-amine cross-linked networks. The experimental design involved variations in polymer network cross-link density, poragen composition, poragen level, and cure temperature. A total of 216 unique compositions were prepared. Changes in opacity of the blends as they cured were monitored visually. Morphology was characterized using a scanning electron microscope on a subset of the 216 samples. The results obtained allowed for the identification of compositional variables and process variables that enabled the production of porous networks.

Keywords: high-throughput, chemically induced phase separation, porous polymer, poragen