@article { ISI:000240258600018, title = {Crystallization and phase transformation kinetics of poly(1-butene)/MWCNT nanocomposites}, journal = {Polymer}, volume = {47}, number = {18}, year = {2006}, month = {AUG}, pages = {6414-6421}, publisher = {ELSEVIER SCI LTD}, type = {Article}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND}, abstract = {

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.

}, keywords = {MWCNT, Phase transformation, poly(1-butene)}, issn = {0032-3861}, doi = {10.1016/j.polymer.2006.07.011}, author = {Wanjale, Santosh D. and Jog, Jyoti Prakash} } @article { ISI:000241854900005, title = {Viscoelastic and dielectric behavior of poly(1-butene)/multiwalled carbon nanotube nanocomposites}, journal = {Journal of Macromolecular Science Part B-Physics}, volume = {45}, number = {6}, year = {2006}, month = {NOV}, pages = {1053-1064}, publisher = {TAYLOR \& FRANCIS INC}, type = {Article}, address = {325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA}, abstract = {

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.

}, keywords = {Dielectric, MWCNT, poly(1-butene), viscoelastic}, issn = {0022-2348}, doi = {10.1080/00222340600929691}, author = {Wanjale, Santosh D. and Jog, Jyoti Prakash} } @article { ISI:000251722700028, title = {Assessing feasibility of polyarylate-clay nanocomposites towards improvement of gas selectivity}, journal = {Journal of Membrane Science}, volume = {306}, number = {1-2}, year = {2007}, month = {DEC}, pages = {277-286}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

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.

}, keywords = {Gas permeation, Nanocomposites, polyarylates, selectivity, solution intercalation}, issn = {0376-7388}, doi = {10.1016/j.memsci.2007.09.001}, author = {Bhole, Yogesh S. and Wanjale, Santosh D. and Kharul, Ulhas K. and Jog, Jyoti Prakash} } @article { ISI:000257321700001, title = {Poly(4-methyl-1-pentene)/MWNT nanocomposites}, journal = {E-Polymers}, year = {2008}, month = {JUL}, pages = {079}, publisher = {EUROPEAN POLYMER FEDERATION}, address = {1, QUAI LEZAY-MARNESIA, F067000 STRASBOURG, FRANCE}, abstract = {

Nanocomposites of poly(4-methyl-1-pentene) (PMP) with various weight fractions of multiwall carbon nanotubes (MWNT{\textquoteright}s) were prepared by melt compounding. The nanocomposites are characterized for structure using scanning electron microscopy. The viscoelastic behavior of the nanocomposites is investigated in solid as well as melt state. The study reveals a significant increase in storage modulus especially in the rubbery regime of the polymer matrix and reduced tan delta. Rheological properties in melt show that the complex viscosity and shear storage modulus are increased as a result of incorporation of MWNT. A systematic decrease in the cross over frequency is noted which is attributed to the increased relaxation time. In dielectric analysis, composition dependent enhanced permittivity and conductivity are observed. The thermal stability of the polymer is found to be significantly improved in presence of MWNT{\textquoteright}s.

}, issn = {1618-7229}, author = {Patil, Prashant A. and Wanjale, Santosh D. and Jog, Jyoti Prakash} } @article { ISI:000329153300077, title = {Morphology, polymorphism, and metal ion adsorption studies of electrospun nanofibers based on pvdf and organically modified layered double hydroxide}, journal = {Journal of Applied Polymer Science}, volume = {130}, number = {6}, year = {2013}, month = {DEC}, pages = {4508-4515}, publisher = {WILEY-BLACKWELL}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {

Nonwoven nanofiber mats of polyvinylidene fluoride (PVDF) with modified layered double hydroxide (MLDH) were prepared by electrospinning. The fiber morphology was studied using scanning electron microscopy. X-ray diffraction and FTIR spectroscopy was used to characterize the polymorphism in electrospun mats. Fibers of diameter in the range 80-800 nm with beads of about 2-3 mu m size were observed for pure PVDF, while in case of PVDF/MLDH nanocomposites the number and size of beads were found to be significantly reduced. Uniform and fine nanofibers were obtained at lower content of MLDH, but slightly rough surface was seen for higher content. FTIR and X-ray diffraction patterns signify various crystalline forms of electrospun PVDF. The content of polar -crystalline phase of PVDF, which exhibit piezo and ferroelectric properties was found to be enhanced significantly due to reinforcement of MLDH. Use of these nanofiber mats for heavy metal Cu (II) removal was explored. (c) 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4508-4515, 2013

}, keywords = {Adsorption, electrospinning, fibers}, issn = {0021-8995}, doi = {10.1002/app.39729}, author = {Birajdar, Mallinath S. and Wanjale, Santosh D. and Lonkar, Sunil P.} }