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Abstract Polyimides (PI) synthesized from 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride (6FDA) with various diamines have been frequently studied as gas separation membranes. The use of 6FDA in polyimides creates a bent structure than can increase fractional free volume (FFV) and gas permeability. Here, we demonstrate that 6FDA is also a useful building block for PI‐ionene materials, which contain cations directly within the polymer backbone. These new 6FDA‐containing PI‐ionenes were combined with several different imidazolium ionic liquids (ILs) to form thin membranes. The thermal properties of all the derivatives were investigated to determine the relationship between regiochemistry and degradation as well as the intermolecular forces that are present within these structures. The gas separation properties of these 6FDA‐containing PI‐ionene + IL materials were investigated, showing modest CO2permeabilities similar to other polyimide‐ionenes and CO2/CH4and CO2/N2permselectivities that were relatively higher than other polyimide‐ionenes.
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Recent development of polyimides: Synthesis, processing, and application in gas separation
Abstract High‐performance polymers have been concomitant with advanced technology for half a century. With the advancement of synthetic chemistry, the recent development of high‐performance polymers has provided superior properties and enabled wide applications. This article reviews recent research progress in aromatic high‐performance polymers. Particularly, we focus on the synthesis and processing of polyimides, as well as the application in gas separation membranes. We begin with a brief introduction to highlight important history and physiochemical characteristics of polyimides. Then, we review the various synthesis methods, followed by recent advances for improving processability. Finally, we evaluate the use of high‐performance polymers in gas separation membranes with focus given to the key issues of plasticization and aging. Overall, the information presented herein provides an up‐to‐date overview of high‐performance polymers, polyimides particularly, and serves as a guide for further research involving the applications in membrane technologies.
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- Award ID(s):
- 1752611
- PAR ID:
- 10450885
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Polymer Science
- Volume:
- 59
- Issue:
- 11
- ISSN:
- 2642-4150
- Format(s):
- Medium: X Size: p. 943-962
- Size(s):
- p. 943-962
- Sponsoring Org:
- National Science Foundation
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