Polymers with Cavities Tuned for Fast Selective Transport of Small Molecules and Ions
Ho Bum Park,1,2
Chul Ho Jung,1
Young Moo Lee,1*
Anita J. Hill,3
Steven J. Pas,3
Stephen T. Mudie,3
Elizabeth Van Wagner,2
Benny D. Freeman,2
David J. Cookson4
Within a polymer film, free-volume elements such as pores and channels typically have a wide range of sizes and topologies. This broad range of free-volume element sizes compromises a polymer's ability to perform molecular separations. We demonstrated free-volume structures in dense vitreous polymers that enable outstanding molecular and ionic transport and separation performance that surpasses the limits of conventional polymers. The unusual microstructure in these materials can be systematically tailored by thermally driven segment rearrangement. Free-volume topologies can be tailored by controlling the degree of rearrangement, flexibility of the original chain, and judicious inclusion of small templating molecules. This rational tailoring of free-volume element architecture provides a route for preparing high-performance polymers for molecular-scale separations.
1 School of Chemical Engineering, Hanyang University, Seoul 133-791, Korea.
2 Center for Energy and Environmental Resources and Department of Chemical Engineering, The University of Texas, Austin, TX 78758, USA.
3 The Commonwealth Scientific and Industrial Research Organization (CSIRO) Materials Science and Engineering, Private Bag 33, S Clayton, VIC 3169, Australia.
4 Australian Synchrotron Research Program, Building 434, 9700 South Cass Avenue, Argonne, IL 60439, USA.
* To whom correspondence should be addressed. E-mail: ymlee{at}hanyang.ac.kr
