01572nas a2200253 4500008004100000022001400041245010500055210006900160260007900229300001400308490000700322520060600329653003700935653003000972653002601002653002101028100002601049700002201075700002401097700001801121700002201139700002501161856013201186 2010 eng d a1388-248100aDirect transfer of micro-molded electrodes for enhanced mass transport and water management in PEMFC0 aDirect transfer of micromolded electrodes for enhanced mass tran a360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USAbELSEVIER SCIENCE INCcNOV a1638-16410 v123 a

Soft lithography technique is used to micropattern the electrodes on the electrolyte membrane of polymer electrolyte fuel cell (PEMFC) in order to alleviate the issues due to poor water management and inadequate reactant distribution in the fuel cell environment. Membrane electrode assembly with the micropatterned electrode has shown an increase in power density at a higher temperature as well as at a higher relative humidity when compared to a flat electrode. Consistency in cell performance is observed in the case of micropatterned electrodes. (C) 2010 Elsevier B.V. All rights reserved.

10aBipolar plate-less PEM fuel cell10aMicropatterned electrodes10aMicrotransfer molding10aSoft lithography1 aDeshmukh, Ashvini, B.1 aKale, Vinayak, S.1 aDhavale, Vishal, M.1 aSreekumar, K.1 aVijayamohanan, K.1 aShelke, Manjusha, V. uhttps://library.ncl.res.in/content/direct-transfer-micro-molded-electrodes-enhanced-mass-transport-and-water-management-pemfc-002350nas a2200193 4500008004100000022001400041245013500055210006900190260011000259300001600369490000600385520151900391100002101910700002701931700002701958700001801985700002202003856013102025 2014 eng d a2050-748800aNew approach of blending polymeric ionic liquid with polybenzimidazole (PBI) for enhancing physical and electrochemical properties0 aNew approach of blending polymeric ionic liquid with polybenzimi aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJUN a14449-144580 v23 a

Although the use of ionic liquids (IL) in polymeric membranes is known to elevate the electrochemical performance for proton exchange membrane-based fuel cells (PEMFC), they suffer from drawbacks such as IL drain and lowering in mechanical properties that lead to deterioration in PEMFC performance. To mitigate these issues, we report, for the first time, the use of polymeric ionic liquid (PIL), namely, poly(diallyl dimethyl ammonium trifluoride methane sulphonate) (P[DADMA][TFMS]) to be blended with polybenzimidazole (PBI-I) as a membrane material for PEMFC. PBI-I and (P[DADMA][TFMS]) were chosen because they form miscible blends and are suitable for acid doping as a matrix, which can eventually be used as proton conductor. The structure, miscibility and inter-polymer interactions were studied by infrared (IR) spectroscopy and differential scanning calorimetry (DSC). The increase in proton conduction in comparison to the PBI membranes was observed due to the presence of ionic groups of PILs in blend membranes. With the increase in PIL content, the proton conductivity of the composite membranes gradually increased from 0.04 S cm(-1) for PBI to 0.07 S cm(-1) for the blend membrane at 150 degrees C. The MEAs were fabricated with PBI-I, PBI-PIL15, PBI-PIL25 and PBI-PIL35. Corresponding single cells were successfully tested at temperatures of 160 degrees C. The maximum power density and current density obtained were 515 mW cm(-2) and 1632 mA cm(-2), respectively, for PBI-PIL25-based MEA.

1 aRewar, Anita, S.1 aChaudhari, Harshal, D.1 aIllathvalappil, Rajith1 aSreekumar, K.1 aKharul, Ulhas, K. uhttps://library.ncl.res.in/content/new-approach-blending-polymeric-ionic-liquid-polybenzimidazole-pbi-enhancing-physical-and-002117nas a2200217 4500008004100000022001400041245008500055210006900140260006700209300001200276490000700288520132500295653001701620653002101637653003801658100002501696700002401721700001801745700001701763856011901780 2015 eng d a0887-624X00aIonic conductivity probed in main chain liquid crystalline azobenzene polyesters0 aIonic conductivity probed in main chain liquid crystalline azobe a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcMAR a629-6410 v533 a

Three main chain thermotropic liquid crystalline (LC) azobenzene polymers were synthesized using the azobenzene twin molecule (P4P) having the structure Phenylazobenzene-tetraethyleneglycol-Phenylazobenzene as the AA monomer and diols like diethylene glycol, tetraethylene glycol (TEG), and hexaethylene glycol as the BB comonomer. Terminal C(O)OMe units on P4P facilitated transesterification with diols to form polyesters. All polymers exhibited stable smectic mesophases. One of the polymers, Poly(P4PTEG) was chosen to prepare composite polymer electrolytes with LiCF3SO3 and ionic conductivity was measured by ac impedance spectroscopy. The polymer/0.3 Li salt complex exhibited a maximum ionic conductivity in the range of 10(-5) S cm(-1) at room temperature (25 degrees C), which increased to 10(-4) S cm(-1) above 65 degrees C. The temperature dependence of ionic conductivity was compared with the phase transitions occurring in the sample and it was observed that the glass transition had a higher influence on the ionic conductivity compared to the ordered LC phase. Reversible ionic conductivity switching was observed upon irradiation of the polymer/0.3 Li salt complex with alternate UV and visible irradiation. (c) 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 629-641

10aazo polymers10aglass transition10aliquid-crystalline polymers (LCP)1 aNardele, Chinmay, G.1 aDhavale, Vishal, M.1 aSreekumar, K.1 aAsha, S., K. uhttps://library.ncl.res.in/content/ionic-conductivity-probed-main-chain-liquid-crystalline-azobenzene-polyesters-002260nas 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

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.

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-002016nas a2200205 4500008004100000022001400041245010700055210006900162260000900231300001600240490000700256520126800263100002301531700004001554700001801594700001801612700001801630700003001648856013201678 2023 eng d a1144-054600aDonor-acceptor-based two-dimensional polymer as a supercapacitor electrode with long cycling stability0 aDonoracceptorbased twodimensional polymer as a supercapacitor el cOCT  a18049-180540 v473 a

The high demand for energy and energy-storage devices urged organic 2D polymers as a potential candidate in this area. One of the major attractions of 2D polymers in electrochemical applications is their long cycling stability due to their rigid and porous structure. Herein, we developed a 2D polymer comprised of donor-acceptor units exhibiting reasonably good performance as a supercapacitor. The 2D polymer displayed a maximum specific capacitance of 218 F g-1 at a current rate of 0.1 A g-1, a higher power density of 4648.35 W kg-1, and an energy density of 7.05 W h kg-1. In a cycling stability test, it demonstrated a capacitance retention of 70% over 10 000 continuous charge-discharge cycles at a current rate of 2.5 A g-1. Such long cycling stability was attributed to the donor-acceptor units and the crystalline nature of the polymer. The sensible selection of the building blocks of the 2D polymers is crucial for the performance and hence provides scope for improvement. An organic donor-acceptor-based 2D polymer, a promising candidate for energy storage devices, displays a specific capacitance of 218 F g-1, a power density of 4648.35 W kg-1, an energy density of 7.05 W h kg-1, and a capacitance retention of 70% over 10 000 cycles.

1 aBhagyasree, T., M.1 aPuthiyaveetil, Priyanka, Pandinhare1 aKumar, Viksit1 aAsokan, Kiran1 aSreekumar, K.1 aBabu, Sukumaran, Santhosh uhttps://library.ncl.res.in/content/donor-acceptor-based-two-dimensional-polymer-supercapacitor-electrode-long-cycling-stability