02269nas a2200241 4500008004100000022001400041245010000055210006900155260007300224300001200297490000800309520138900317653001901706653001901725653001701744653001601761653002701777100002201804700002501826700002201851700002401873856013001897 2007 eng d a0376-738800aAssessing feasibility of polyarylate-clay nanocomposites towards improvement of gas selectivity0 aAssessing feasibility of polyarylateclay nanocomposites towards  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcDEC a277-2860 v3063 a

Polymer-clay nanocomposites are well known to reduce the penetrant permeability by following tortuous path. Effects of such reduction in gas permeability on variation in selectivity of nanocomposites prepared using a high permeability polymer were examined. The polyarylate: poly (tetramethyl bisphenolA-iso/terephthalate) that exhibits high permeability and moderate selectivity was chosen for making nanocomposites with two organically modified clays (Cloisite 6A and 10A) by solution intercalation method. The nanocomposite formation for various clay loadings (3, 5 and 7% w/w) in polyarylate was ascertained by change in physical properties (X-ray diffraction, DMA, TEM). Behavior of solution viscosity and nanocomposite density indicated existence of polymer-clay layer interactions. As anticipated, though the gas permeability of pure gases, viz., He, N-2, CH4 and CO2 exhibited decrease, it was not monotonous. This decrease was more for larger gases (N-2, CH4 and CO2) in comparison to the decrease for smaller gas (He) permeability. This led to a decrease in CO2/N-2 and CO2/CH4 selectivities and increase in He/CO2 selectivity; while He/CH4 selectivity was increased substantially at 7% clay loading. This variation indicated feasibility of nanocomposites formation as a tool for improving selectivity of certain gas pairs. (c) 2007 Elsevier B.V. All rights reserved.

10aGas permeation10aNanocomposites10apolyarylates10aselectivity10asolution intercalation1 aBhole, Yogesh, S.1 aWanjale, Santosh, D.1 aKharul, Ulhas, K.1 aJog, Jyoti, Prakash uhttp://library.ncl.res.in/content/assessing-feasibility-polyarylate-clay-nanocomposites-towards-improvement-gas-selectivity-001893nas a2200205 4500008004100000022001400041245014500055210006900200260007100269300001400340490000600354520106200360100002101422700002201443700002901465700002401494700002201518700003001540856011701570 2010 eng d a1948-718500aArtificially designed membranes using phosphonated multiwall carbon nanotube-polybenzimidazole composites for polymer electrolyte fuel cells0 aArtificially designed membranes using phosphonated multiwall car a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUL a2109-21130 v13 a

The ability of phosphonated carbon nanotubes to offer an unprecedented approach to tune both proton-conductivity and mechanical stability of hybrid polymer electrolytes based on the polybenzimidazole membrane is demonstrated for fuel cell applications. The covalent attachment between the amino group of the 2-aminoethylphosphonic acid precursor and CNTs has been confirmed by NMR and IR experiments, while EDAX analysis indicates that one out of every 20 carbon atoms is in the CNT is functionalized. Proton conductivity of the composite membrane shows a remarkable 50% improvement in performance while a maximum power density of 780 and 600 mW cm(-2) is obtained for the composite and pristine membranes, respectively. Finally, the ultimate strength determined for the composite and pristine membranes is 100 and 65 MPa, respectively, demonstrating the superiority of the composite. This study opens up a new strategy to systematically tune the properties of polymer electrolytes for special applications by using appropriately functionalized CNTS.

1 aKannan, Ramaiyan1 aAher, Pradnya, P.1 aPalaniselvam, Thangavelu1 aKurungot, Sreekumar1 aKharul, Ulhas, K.1 aPillai, Vijayamohanan, K. uhttp://library.ncl.res.in/content/artificially-designed-membranes-using-phosphonated-multiwall-carbon-nanotube-001760nas a2200241 4500008004100000022001400041245010700055210006900162260000800231300001400239490000700253520094400260653002101204653001701225653001601242100002801258700002601286700001701312700001801329700002201347700001801369856013101387 2022 eng d a1546-542X00aAddressing challenges in sealing of scalable multifiber module for O-2 enrichment using LSCF membranes0 aAddressing challenges in sealing of scalable multifiber module f cMAY a1561-15710 v193 a

Scalable and multifiber modules in oxygen separation face huge challenges due to difficulty in integrating all the necessary components, especially in sealing the fibers in a gas tight module. Here, we report our findings on design and fabrication of a multifiber La0.6Sr0.4Co0.2Fe0.8O3-delta (LSCF)-based module, which can be scaled up. The focus is on sealing ceramic-metal interfaces by layering of sealants of varying thermal properties. We have also incorporated the use of dead ended fibers to minimize ceramic-metal interfaces in the hot zones and present a new method for dead ending by flame melting. Pressurizing the air inlet feed from either bore side or shell side is detrimental to the structural integrity of the fibers. A thorough characterization of the fresh and spent fibers is also carried out using X-ray tomography and electron microscopy, which indicates effect of temperature and pressure on the fibers.

10aCharacterization10apermeability10aPerovskites1 aJogdand, Shunottara, M.1 aBedadur, Prachiti, R.1 aTorris, Arun1 aAgrawal, Ravi1 aKharul, Ulhas, K.1 aDevi, Nandini uhttp://library.ncl.res.in/content/addressing-challenges-sealing-scalable-multifiber-module-o-2-enrichment-using-lscf-membranes