02012nas a2200229   4500008004100000022001400041245009400055210006900149260010600218300001400324490000700338520114600345653001701491653002101508653002401529653001601553100002201569700002201591700001901613700002301632856012701655       2005                        eng d  a0014-305700aBenzoylation of polyphenylene oxide: characterization and gas permeability investigations0 aBenzoylation of polyphenylene oxide characterization and gas per  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcOCT  a2461-24710 v413 a<p>Benzoylation of polyphenylene oxide (PPO) was carried out with aromatic acid chlorides bearing specific groups at para-position (H methyl, Br, Cl and nitro), which differ in their polarity and bulk. The reaction conditions were optimized individually to get the high degree of substitution. These materials were characterized for thermal as well as other physical properties that are known to affect the gas permeation. In a series investigated, the nitrobenzoyl substitution on PPO resulted in the highest increase in glass transition temperature and the lowest thermal stability. An estimation of the packing density parameters-fractional free volume by density measurement and the d-spacing by X-ray diffraction analysis showed an increase in the packing density. The gas permeability was found to decrease in all the cases of benzoylation. The helium and oxygen based selectivities were increased, while CO2 based selectivities were decreased. The unusual trend observed in the gas permeation properties is explained on the basis of nature of substituent and the degree of substitution. (c) 2005 Elsevier Ltd. All rights reserved.</p>10abenzoylation10aGas permeability10apolyphenylene oxide10aselectivity1 aBhole, Yogesh, S.1 aKharul, Ulhas, K.1 aSomani, S., P.1 aKumbharkar, S., C.  uhttps://library.ncl.res.in/content/benzoylation-polyphenylene-oxide-characterization-and-gas-permeability-investigations-002003nas a2200241   4500008004100000022001400041245007700055210006900132260006800201300001400269490000800283520114800291653001801439653002301457653003101480653002501511653002001536100002701556700002301583700002201606700002201628856011101650       2006                        eng d  a0021-899500aSurface modification of polyacrylonitrile based ultrafiltration membrane0 aSurface modification of polyacrylonitrile based ultrafiltration   a111 RIVER ST, HOBOKEN, NJ 07030 USAbJOHN WILEY & SONS INCcSEP  a4378-43850 v1013 a<p>Ultrafiltration membrane based on polyacrylonitrile prepared by phase inversion method using zinc chloride as an additive showed more than 90% rejection for BSA and 90-110 Im(-2) h(-1) water flux. The surface modification of this membrane was studied using ethanolamine, triethylamine, sodium hydroxide, and potassium hydroxide solutions. The effect of base treatment time and temperature on water flux and rejection was investigated. The membranes exhibited swelling by NaOH treatment followed by deswelling by HCl post-treatment, similar to pH responsive membranes. The treatment by organic as well as inorganic bases improved water flux with a slight lowering in BSA rejection by dead-end mode type treatment. A 230% increase in water flux was achieved by sodium hydroxide treatment in crossflow mode without a noticeable pore swelling by SEM. The contact angle of the modified membranes was decreased as compared to the unmodified one indicating appreciable surface modification. As the treatment time or temperature increased, the ESCA analysis showed increased population of Na-carboxylate groups. (c) 2006 Wiley Periodicals, Inc.</p>10aBSA rejection10achemical treatment10apolyacrylonitrile membrane10asurface modification10aUltrafiltration1 aLohokare, Harshada, R.1 aKumbharkar, S., C.1 aBhole, Yogesh, S.1 aKharul, Ulhas, K.  uhttps://library.ncl.res.in/content/surface-modification-polyacrylonitrile-based-ultrafiltration-membrane-002270nas a2200241   4500008004100000022001400041245010000055210006900155260007300224300001200297490000800309520138900317653001901706653001901725653001701744653001601761653002701777100002201804700002501826700002201851700002401873856013101897       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<p>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.</p>10aGas permeation10aNanocomposites10apolyarylates10aselectivity10asolution intercalation1 aBhole, Yogesh, S.1 aWanjale, Santosh, D.1 aKharul, Ulhas, K.1 aJog, Jyoti, Prakash  uhttps://library.ncl.res.in/content/assessing-feasibility-polyarylate-clay-nanocomposites-towards-improvement-gas-selectivity-002613nas a2200265   4500008004100000022001400041245009200055210006900147260007300216300001200289490000800301520170400309653001402013653001302027653001502040653001702055653001302072100002502085700002202110700002202132700002202154700002302176700002602199856012202225       2007                        eng d  a0376-738800aGas sorption and transport in polyarylates: effect of substituent symmetry and polarity0 aGas sorption and transport in polyarylates effect of substituent  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcOCT  a244-2510 v3033 a<p>The gas sorption properties of polyarylates based on bisphenol-A possessing symmetric/asymmetric substitution by nonpolar -CH3 group and symmetrically linked terephthalic acid were examined. The effects of substitution of polar bromine on terephalic acid moiety of polyarylate based on asymmetrically substituted bisphenol were also studied for physical, sorption and transport properties. The estimation of dual mode sorption parameters, solubility and diffusion coefficient revealed that nature of the substituent and substitution type plays a crucial role in depicting permeation properties. An asymmetric substitution by -CH3 group increased solubility coefficient of pure gases (N-2, O-2, CH4 and CO2) up to 27% and symmetric substitution increased the same up to 106%. This was coupled with 7-35% increase in solubility selectivity in both cases of substitution, which ascertained the usefulness of methyl group substitution in polyarylates based on terephalic acid. The pressure dependency of solubility coefficients and solubility selectivity was also investigated for these polyarylates. The sorption and transport properties of these polyarylates correlated well with physical properties of polyarylates and gases studied. The sorption/desorption kinetics of symmetrically substituted TMBisA-T was performed in order to deduce time dependent sorption behavior and to evaluate diffusivity coefficient. The apparent diffusion coefficients from sorption kinetics, desorption kinetics and from steady-states permeation-sorption were compared. The diffusion coefficients of CH4 and N-2 deduced by these methods correlated well with each other. (C) 2007 Elsevier B.V. All rights reserved.</p>10aDiffusion10akinetics10apermeation10apolyarylates10aSorption1 aKaradkar, Prasad, B.1 aKharul, Ulhas, K.1 aBhole, Yogesh, S.1 aBadhe, Yogesh, P.1 aTambe, Sanjeev, S.1 aKulkarni, Bhaskar, D.  uhttps://library.ncl.res.in/content/gas-sorption-and-transport-polyarylates-effect-substituent-symmetry-and-polarity-002118nas a2200229   4500008004100000022001400041245010000055210006900155260010600224300001400330490000700344520125800351653001401609653001401623653001501637653002401652653001301676100002201689700002501711700002201736856013001758       2007                        eng d  a0014-305700aNitration and amination of polyphenylene oxide: synthesis, gas sorption and permeation analysis0 aNitration and amination of polyphenylene oxide synthesis gas sor  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcAPR  a1450-14590 v433 a<p>A high degree of nitration of polyphenylene oxide (PPO) was successfully achieved by carefully optimizing synthetic protocol. The reduction of nitro group to amino could be done quantitatively. The physical properties of formed polymers were investigated and correlated with gas sorption and permeation properties. The formed polymers were amorphous in nature as revealed by wide angle X-ray diffraction spectra. An increase in the packing density in comparison to unsubstituted PPO as a result of induced polarity was indicated by lowering of fractional free volume and d-spacing. The substitution by either nitro or amino group increased the chain stiffness as revealed by the dynamic mechanical analysis. Though both, nitro and amino group substitution on PPO led to a decrease in pure gas permeability, the selectivity of various gas pairs was increased by these substitutions. The gas sorption analysis revealed that both, solubility selectivity and diffusivity selectivity were increased by these polar group substitutions. The nitro group substitution was more effective in improving solubility selectivity, while amino group substitution was more effective in improving diffusivity selectivity. (C) 2007 Elsevier Ltd. All rights reserved.</p>10aAmination10anitration10apermeation10apolyphenylene oxide10aSorption1 aBhole, Yogesh, S.1 aKaradkar, Prasad, B.1 aKharul, Ulhas, K.  uhttps://library.ncl.res.in/content/nitration-and-amination-polyphenylene-oxide-synthesis-gas-sorption-and-permeation-analysis01613nas a2200241   4500008004100000022001400041245013800055210006900193260008600262300001200348490000700360520069800367653001901065653001701084653001301101653001701114653001701131100002501148700002201173700002701195700002201222856012701244       2010                        eng d  a0149-639500aPolyarylate based thin film composite (TFC) membranes: effects of coating parameters, gutter layer, and intrinsic material properties0 aPolyarylate based thin film composite TFC membranes effects of c  a325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USAbTAYLOR & FRANCIS INCcJAN  a163-1710 v453 a<p>Investigations in thin film composite (TFC) membrane formation with polyacrylonitrile ultrafiltration membrane as a support and three polyarylates with sequentially increased polarity are reported. Effects of TFC membrane preparation parameters viz., concentration of the coating solution, dip time, presence of solvent in pores of UF membrane support, and presence of the gutter layer were examined towards the formation of the selective skin layer, which was assessed by gas permeation analysis. TFC membranes prepared using dimethyl bisphenol-A based polyarylate exhibited similar to 3 orders of magnitude higher permeability and comparable selectivity as that of its dense membrane.</p>10aGas permeation10agutter layer10apolarity10apolyarylates10aTFC membrane1 aChendake, Yogesh, J.1 aBhole, Yogesh, S.1 aLohokare, Harshada, R.1 aKharul, Ulhas, K.  uhttps://library.ncl.res.in/content/polyarylate-based-thin-film-composite-tfc-membranes-effects-coating-parameters-gutter-002308nas a2200241   4500008004100000022001400041245009600055210006900151260007300220300001000293490000800303520143000311653001301741653002301754653002401777653002701801653002001828100002701848700002201875700002001897700002201917856012701939       2011                        eng d  a0011-916400aPoly(acrylonitrile) based ultrafiltration membranes: optimization of preparation parameters0 aPolyacrylonitrile based ultrafiltration membranes optimization o  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcNOV  a46-530 v2823 a<p>Supported ultrafiltration (UF) membranes based on poly(acrylonitrile) were prepared while varying crucial parameters responsible for controlling membrane porosity, viz.; polymer concentration, solvent and additives in the dope solution. Insight into membrane porosity and morphology was obtained by water flux, solute rejection, bubble point, pore size distribution, SEM and AFM analyses. It was found that merely increasing polymer concentration does not necessarily reduce pore size of membranes. Among four solvents used for the dope solution preparation, N-methyl pyrrolidone was found to offer membranes with optimal combination of flux and rejection of various solutes. Some of the PAN(17) (17% w/w PAN concentration in the dope solution) membranes prepared using organic acid as the additive (citric acid, tartaric acid or maleic acid) offered 1.2-1.7 times higher flux than the membrane prepared using inorganic salt, ZnCl2 as an additive. The porosity of PAN(17) membrane prepared using CA as an additive was larger as compared to membrane prepared using ZnCl2 as an additive. Atomic force microscopy (AFM) analysis of this membrane exhibited higher surface roughness as compared to the ZnCl2 based membrane. Both these membranes exhibited bacteria (E. Coli) log reduction value (LRV) of at least 6; depicting applicability of these membrane for water disinfection. (C) 2011 Elsevier B.V. All rights reserved.</p>10aAdditive10aBacteria rejection10aPoly(acrylonitrile)10aPore size distribution10aUltrafiltration1 aLohokare, Harshada, R.1 aBhole, Yogesh, S.1 aTaralkar, Suyog1 aKharul, Ulhas, K.  uhttps://library.ncl.res.in/content/polyacrylonitrile-based-ultrafiltration-membranes-optimization-preparation-parameters-0