02155nas a2200193 4500008004100000022001400041245009300055210006900148260009900217300001400316490000700330520139800337653001001735653002501745653001901770100002501789700002401814856012301838 2006 eng d a0032-386100aCrystallization and phase transformation kinetics of poly(1-butene)/MWCNT nanocomposites0 aCrystallization and phase transformation kinetics of poly1butene aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcAUG a6414-64210 v473 a

Poly(1-butene)/MWCNT nanocomposites were prepared by simple melt processing technique. Crystallization, crystal-to-crystal phase transformation and spherulitic morphology were studied using differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD) and optical microscopy (OM). The non-isothermal crystallization exhibited higher values of Z, derived from Avrami theory and lower values of F(T) obtained from Avrami-Ozawa analysis, while the isothermal crystallization revealed a significant increase in crystallization temperatures and lower crystallization half times compared to pristine PB. The observed changes in the crystallization kinetics were ascribed to the enhanced nucleation of PB in the presence of MWCNT. The nucleating activity calculated from the non-isothermal crystallization data revealed that the MWCNTs provide an active surface for the nucleation of PB. The optical micrographs exhibited significantly smaller crystallites with disordered morphology for the nanocomposites compared to the well defined spherulitic morphology for pristine PB. The rate of phase transformation from kinetically favored tetragonal to thermodynamically stable hexagonal form was noticeably enhanced as evidenced by the reduction in the half time for phase transformation from 58 h to 25 h for PB reinforced with 7% MWCNT. (c) 2006 Elsevier Ltd. All rights reserved.

10aMWCNT10aPhase transformation10apoly(1-butene)1 aWanjale, Santosh, D.1 aJog, Jyoti, Prakash uhttp://library.ncl.res.in/content/crystallization-and-phase-transformation-kinetics-poly1-butenemwcnt-nanocomposites-001687nas a2200205 4500008004100000022001400041245010200055210006900157260008600226300001400312490000700326520092100333653001501254653001001269653001901279653001701298100002501315700002401340856011701364 2006 eng d a0022-234800aViscoelastic and dielectric behavior of poly(1-butene)/multiwalled carbon nanotube nanocomposites0 aViscoelastic and dielectric behavior of poly1butenemultiwalled c a325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USAbTAYLOR & FRANCIS INCcNOV a1053-10640 v453 a

Linear viscoelastic properties and dielectric behavior of poly(1-butene)/multiwalled carbon nanotube (MWCNT) nanocomposites were investigated. Dynamic mechanical analysis showed significant increase in storage modulus in the rubbery regime. The tan delta peak temperature remained constant; however, the peak intensity was lowered for the nanocomposites. In melt rheological studies the nanocomposites showed a shift in crossover frequency to the lower side, suggesting delayed relaxation of the molecular chains in the presence of MWCNT and this shift was found to depend on the content of MWCNT. The dielectric constant increased from 2.2 to 70 for the nanocomposite with 7 wt. % MWCNT. The electrical conductivity increased significantly, from 10(-15) to 10(-3) S/cm. The results of rheology and dielectric studies indicate that a percolation network is formed that is responsible for the observed changes.

10aDielectric10aMWCNT10apoly(1-butene)10aviscoelastic1 aWanjale, Santosh, D.1 aJog, Jyoti, Prakash uhttp://library.ncl.res.in/content/viscoelastic-and-dielectric-behavior-poly1-butenemultiwalled-carbon-nanotube-003338nas a2200253 4500008004100000022001400041245019100055210006900246260010600315300001400421490000700435520231200442653003202754653001002786653003002796653001702826653001002843100002402853700002502877700001902902700002202921700002402943856011702967 2010 eng d a0013-468600aPt-MoOx-carbon nanotube redox couple based electrocatalyst as a potential partner with polybenzimidazole membrane for high temperature polymer electrolyte membrane fuel cell applications0 aPtMoOxcarbon nanotube redox couple based electrocatalyst as a po aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcMAR a2878-28870 v553 a

A redox couple based electrocatalyst comprising of Pt-Multi Wall Carbon NanoTube (Pt-MWCNT) promoted with molybdenum oxide (MoOx, 2 < x < 3) nanoparticles was prepared. The objective was to effectively organize the Pt-MoOx interface on the smooth MWCNT surface to overcome the practical difficulties associated with establishing such interface with Pt dispersed on carbon morphologies possessing surface irregularities. The present study revealed the importance of stringent controlling of the additive level for maintaining a balanced bifunctional behavior of the catalyst combination through the synergistic effects by the components and the need of a proton conducting membrane operable at high temperature to get better output from the Polymer Electrolyte Membrane Fuel Cell (PEMFC) systems. An indigenously developed polybenzimidazole (PBI) membrane was used to fabricate a membrane electrode assembly (MEA) as it can be operated at higher temperatures compared to that of Nafion membranes. MoOx additive level was carefully controlled by monitoring the active Pt area by cyclic voltammetry. All prepared electrocatalysts were characterized by using HRTEM, XRD and XPS to get information on dispersion and morphology, crystalinity and oxidation state of different elements, respectively. The system prepared with 5% MoOx addition with respect to Pt (hereafter Pt-MoOx(5%)-MWCNT) displayed balanced active Pt area and excellent oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) activities. Rotating Disk Electrode (ROE) system was extensively utilized to understand the ORR kinetics and the favorable role of MoOx as the promoter in the reaction. The kinetic current (j(k)) measured at 0.02 V vs. Hg/Hg2SO4 electrode from the Koutecky-Levich plots was 9 times higher and the apparent activation energy during single cell evaluation was 27 kJ/mol lower for the MoOx promoted system, compared to the system without the additive. A higher operating temperature significantly favored the cell performance by a combined effect of enhancement in proton conductivity of the PBI membrane and possible kinetic benefit by the well postulated oxygen spill over effect by the MoOx type systems in some combinations involving such systems. (C) 2010 Elsevier Ltd. All rights reserved.

10aMethanol oxidation reaction10aMWCNT10aoxygen reduction reaction10aPBI membrane10aPEMFC1 aVellacheri, Ranjith1 aUnni, SreeKuttan, M.1 aNahire, Sandip1 aKharul, Ulhas, K.1 aKurungot, Sreekumar uhttp://library.ncl.res.in/content/pt-moox-carbon-nanotube-redox-couple-based-electrocatalyst-potential-partner-0