01713nas a2200229   4500008004100000245012500041210006900166260000800235300001400243490000700257520090400264100001801168700001901186700002201205700001701227700002201244700002601266700002101292700001801313700002001331856013201351       2018                        eng d00aUltrastable imine-based covalent organic frameworks for sulfuric acid recovery: an effect of interlayer hydrogen bonding0 aUltrastable iminebased covalent organic frameworks for sulfuric   cMAY  a5797-58020 v573 aA rapid and scalable synthesis of six new imine-linked highly porous and crystalline COFs is presented that feature exceptionally high chemical stability in harsh environments including conc. H2SO4 (18M), conc. HCl (12M), and NaOH (9M). This is because of the presence of strong interlayer C-H center dot center dot center dot N hydrogen bonding among the individual layers, which provides significant steric hindrance and a hydrophobic environment around the imine (-C=N-) bonds, thus preventing their hydrolysis in such an abrasive environment. These COFs were further converted into porous, crystalline, self-standing, and crack-free COF membranes (COFMs) with extremely high chemical stability for their potential applications for sulfuric acid recovery. The as-synthesized COFMs exhibit unprecedented permeance for acetonitrile (280 Lm(-2) h(-1) bar(-1)) and acetone (260 Lm(-2) h(-1) bar(-1)).1 aHalder, Arjun1 aKarak, Suvendu1 aAddicoat, Matthew1 aBera, Saibal1 aChakraborty, Amit1 aKunjattu, Shebeeb, H.1 aPachfule, Pradip1 aHeine, Thomas1 aBanerjee, Rahul  uhttps://library.ncl.res.in/content/ultrastable-imine-based-covalent-organic-frameworks-sulfuric-acid-recovery-effect-interlayer