Lu Y. Hu X. Pang Y. Miao J. Zhao J. Nie W. Wang Z. Yan J. text xx 9999 monographic und

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Here, a series of intrinsically microporous polyimides (PIM-PIs) were prepared from norbornane-2-spiro-?-cyclopentanone-??-spiro-2?-norbornane-5,5?,6,6?-tetracarboxylic dianhydride (CpODA) and archetypal contorted diamines, and their microstructures and gas transport properties were systematically investigated and compared with those of the counterparts derived from 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA). For certain diamines, the surface areas, interchain distances, and fractional free volumes (FFV) of the CpODA-derived PIM-PIs were considerably greater than those of the 6FDA-derived ones, and were in the range of 92-567 m2 g?1, 0.575-0.607 nm, and 0.194-0.246, respectively. Consequently, the CpODA-derived PIM-PIs overall displayed higher gas permeabilities and better gas separation performances compared to the 6FDA-derived ones. In particular, CpODA-TBDA2 and CpODA-DAT showed high H2 permeabilities (>600 Barrer) and moderate H2/N2 and H2/CH4 selectivities which approached or even surpassed the corresponding 2008 Robeson upper bounds. The excellent gas separation performance of these CpODA-derived PIM-PIs may be attributed to the contorted and bulky architecture of the CpODA residue, which led to reduced inter- and intra-molecular interactions and the formation of ultramicropores of <0.7 nm. © 2021 Elsevier Ltd ALICYCLIC DIANHYDRIDE GAS SEPARATION PERFORMANCE INTERCHAIN DISTANCE POLYIMIDES OF INTRINSIC MICROPORE STRUCTURE-PROPERTY RELATIONSHIP https://drive.google.com/file/d/1ymuWioxyN0IVCTaH905zXc-R7z2cwb8h/view?usp=drive_link https://drive.google.com/file/d/1ymuWioxyN0IVCTaH905zXc-R7z2cwb8h/view?usp=drive_link 250602 20260521091802.0