02260nas a2200229   4500008004100000022001400041245015100055210006900206260007300275300001000348490000800358520136000366653002901726653001901755653002201774653002701796100002101823700002401844700001801868700002201886856012201908       2015                        eng d  a0376-738800aPolybenzimidazole based polymeric ionic liquids (PILs): effects of controlled degree of N-quaternization on physical and gas permeation properties0 aPolybenzimidazole based polymeric ionic liquids PILs effects of   aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcMAY  a19-270 v4813 a<p>Polymeric ionic liquids (PILs) are gaining increasing attention as potential membrane materials to be employed for CO2 separation. With a goal to improve gas permeability, this work presents a series of film forming PlLs obtained by controlled degree of N-quaternization (DQ) of PBI-BuI using a bulky 4-tertbutylbenzyl group. Concurrent effects of variation in ionic content and bulky group substitution were analyzed for physical and gas permeation properties of the resulting PILs. Attempted structural variations leading to simultaneous increments in ionic content and bulky groups offered amorphous polymers with acceptable thermal stability and non-monotonous chain packing density. Enhancement in pure gas permeability coupled with appreciable selectivity for various gas pairs was in accordance with the packing density variations in the series. Gas permeability showed maxima at DQ of just 13%. This conveyed that effects of bulky group substitution in retarding chain packing are overcome by attractive ionic interactions at much lower DQ in these PILs ionic interactions are thus more predominant in governing chain packing and gas permeation properties. These PILs possessed 3.3-20 times higher CO2 permeability in comparison to their parent PBI-BuI, without a significant loss in selectivity. (C) 2015 Elsevier B.V. All rights reserved.</p>10aDegree of quaternization10aGas permeation10aPolybenzimidazole10aPolymeric ionic liquid1 aRewar, Anita, S.1 aBhavsar, Rupesh, S.1 aSreekumar, K.1 aKharul, Ulhas, K.  uhttps://library.ncl.res.in/content/polybenzimidazole-based-polymeric-ionic-liquids-pils-effects-controlled-degree-n-0