02021nas a2200265 4500008004100000022001400041245011100055210006900166260006700235300001400302490000700316520110900323653000601432653002901438653002801467653001301495653001801508653003701526653001901563653000901582100001701591700001501608700001601623856011601639 2005 eng d a0887-624X00aDesign, syntheses, and characterization of new thermoplastic polyureas based on 3,4-ethylenedioxythiophene0 aDesign syntheses and characterization of new thermoplastic polyu a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcDEC a5823-58300 v433 a

New thermoplastic polyureas labeled PUn (n = 2, 3, 4, 6, 7, 9, or 10), based on 3,4-ethylenedioxythiophene (EDOT) with flexible aliphatic spacers, were synthesized and characterized for the first time. EDOT was chosen as a replacement for the aromatic phenyl group in conventional thermoplastics based on urea linkages to improve solubility without compromising the thermal properties. As synthesized, all the samples exhibited a semicrystalline nature. The glass-transition and melting temperatures showed a strong dependence on the spacer length. A comparison of the thermal properties of these polyureas with the corresponding phenyl analogues indicated that EDOT was a viable heteroatomic analogue of the phenyl group to be inserted into the main-chain polyureas without hampering their thermal stability. The polyureas with spacer lengths greater than hexamethylene formed transparent gels in N-methylpyrrolidone, 1,1,2,2-tetrachloroethane, and dimethyl sulfoxide. The molecular packing of the polyureas was assigned with wide-angle X-ray diffraction studies. (c) 2005 Wiley Periodicals, Inc.

10a310a4-ethylenedioxythiophene10aheteroaromatic polymers10aPolyurea10apolyurea gels10aThermogravimetric analysis (TGA)10athermoplastics10aWAXS1 aOjha, U., P.1 aRamesh, C.1 aKumar, Anil uhttps://library.ncl.res.in/content/design-syntheses-and-characterization-new-thermoplastic-polyureas-based-34-001800nas a2200205 4500008004100000022001400041245009300055210006900148260007500217300001200292490000700304520104700311653001801358653002301376653001801399653001401417100002601431700001601457856012101473 2009 eng d a0095-978200aDramatic change in viscosities of pure ionic liquids upon addition of molecular solvents0 aDramatic change in viscosities of pure ionic liquids upon additi a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGER/PLENUM PUBLISHERScMAY a589-6000 v383 a

Viscosities of binary mixtures of pyridinium based ionic liquids (1-butyl pyridinium tetrafluoroborate, [BP][BF(4)], 1-butyl 3-methyl pyridinium tetrafluoroborate [3-MBP][BF(4)], 1-butyl 4-methyl pyridinium tetrafluoroborate, [4-MBP][BF(4)]), and phosphonium based ionic liquids, (tetrabutyl phosphonium alaninate, [TBP][Ala]; tetrabutyl phosphonium valinate, [TBP][Val]) with the molecular solvents, water, methanol and dichloromethane, have been measured at 298.15 K. A Brookfield ultra-rheometer was employed to measure the reported viscosities. The drop in viscosity in the close vicinity of pure ionic liquid is more prominent in polar solvents like water compared to less polar solvents. The temperature dependence of this observation was also studied for binary mixtures of [4-MBP][BF(4)] with water in range of 298.15-323.15 K. The Vogel-Fulcher-Tamman (VFT) equation was employed to investigate the temperature dependence of the viscosities of pure pyridinium-based ionic liquids in the temperature range from 298.15-323.15 K.

10aionic liquids10aMolecular solvents10aVFT equations10aviscosity1 aKhupse, Nageshwar, D.1 aKumar, Anil uhttps://library.ncl.res.in/content/dramatic-change-viscosities-pure-ionic-liquids-upon-addition-molecular-solvents-001878nas a2200157 4500008004100000022001400041245013800055210006900193260007100262300001200333490000800345520119500353100002601548700001601574856013001590 2011 eng d a1520-610600aDelineating solute-solvent interactions in binary mixtures of ionic liquids in molecular solvents and preferential solvation approach0 aDelineating solutesolvent interactions in binary mixtures of ion a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcFEB a711-7180 v1153 a

The effect of solute-solvent and solvent-solvent interactions on the preferential solvation of solvatochromic indicators in binary mixtures of ionic liquids with molecular solvents has been investigated. The binary mixtures of the pyridinium-based ionic liquids 1-butylpyridinium tetrafluoroborate ([BP][BF4]), 1-butyl-3-methylpyridinium tetrafluoroborate ([3-MBP][BF4]), and 1-butyl-4-methylpyridinium tetrafluoroborate ([4-MBP][BF4]) with molecular solvents like water, methanol, and dichloromethane have been selected for this investigation. The effect of addition of ionic liquids to molecular solvents on the polarity parameters E-T(N), Kamlet-Taft parameters, hydrogen bond donor ability (HBD) (alpha), hydrogen bond acceptor ability (HBA) (beta), and polarizability (pi*) was obtained. The polarity parameters of the mixture display nonideality on addition of ionic liquids to water and dichloromethane. On the other hand, strong synergetic effects were seen in the ionic liquid-methanol binary mixtures. The preferential solvation models have been employed to analyze the collected data in order to achieve information on solute-solvent interactions in these binary mixtures.

1 aKhupse, Nageshwar, D.1 aKumar, Anil uhttps://library.ncl.res.in/content/delineating-solute-solvent-interactions-binary-mixtures-ionic-liquids-molecular-solvents-001862nas a2200169 4500008004100000022001400041245006200055210006100117260011000178300001400288490000700302520122500309100002501534700002601559700001601585856009101601 2012 eng d a1463-907600aDo anions influence the polarity of protic ionic liquids?0 aDo anions influence the polarity of protic ionic liquids aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcDEC a2754-27610 v143 a

Polarity studies in two classes of imidazolium-based protic ionic liquids (PILs) possessing [HSO4](-), [HCOO](-),[CH3COO](-) and [CH3CH2COO](-) anions were carried out using a solvatochromic method from 298.15 to 353.15 K. For 1-methylimidazolium class of PILs, ET(30) was found to be independent over the entire range of temperature, while ET(30) was noted to decrease with a rise in temperature in the case of 1-butylimidazolium class of PILs containing [CH3COO](-) and [CH3CH2COO](-) anions. The ET(30) value decreases in both the classes upon varying the anions ([HSO4](-), [HCOO](-), [CH3COO](-) and [CH3CH2COO](-)). The E-T(30) value is controlled by hydrogen bond acceptor basicity, b, and dipolarity/polarizability, pi*. The E-T(30) value for PILs varies inversely to the strength of the coulombic interaction between ions in PILs. Strong interactions between ions lead to lower E-T(30) values. Unlike the poor thermal effect on E-T(30), the Kamlet-Taft parameters i.e. alpha, beta and pi* have pronounced thermal effect in the imidazolium-based PILs. Variation in the Kamlet-Taft parameters is controlled by the stabilization of ions and the degree of proton transfer from Bronsted acid to Bronsted base.

1 aShukla, Shashi, Kant1 aKhupse, Nageshwar, D.1 aKumar, Anil uhttps://library.ncl.res.in/content/do-anions-influence-polarity-protic-ionic-liquids-001318nas a2200157 4500008004100000022001400041245010300055210006900158260007300227300001000300490000800310520067700318100002500995700001601020856012401036 2013 eng d a0009-261400aDo protic ionic liquids and water display analogous behavior in terms of hammett acidity function?0 aDo protic ionic liquids and water display analogous behavior in  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAPR a12-160 v5663 a

We address an issue whether the strength of carboxylic acids in water is linear with respect to that in ionic liquids. Strength of carboxylic acids in water and different PILs using Hammett function (Ho) has revealed interesting linear correlation between the Ho function for all acids in PILs and PIL-water in spite of large structural and electronic differences. These observations suggest that different structural and electronic features of PILs and water behave analogously towards Ho. This linearity in Ho functions between PILs and PIL-water systems can be used to develop predictive method to calculate Ho values. (c) 2013 Elsevier B.V. All rights reserved.

1 aShukla, Shashi, Kant1 aKumar, Anil uhttps://library.ncl.res.in/content/do-protic-ionic-liquids-and-water-display-analogous-behavior-terms-hammett-acidity-001219nas a2200169 4500008004100000022001400041245008700055210006900142260011000211300001600321490000700337520053700344100001900881700002300900700001600923856011000939 2015 eng d a1463-907600aDeviation of polarity from linearity in liquid mixtures containing an ionic liquid0 aDeviation of polarity from linearity in liquid mixtures containi aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcNOV a31613-316170 v173 a

The physico-chemical properties of liquid mixtures, in general, exhibit deviations from linear behaviour with respect to their composition, arising out of different types of cross-intermolecular interactions (both specific and non-specific). These specific and non-specific interactions can however be monitored to obtain the linear mixing in liquid mixtures using the pseudo-solvent methodology in such a manner that the interactions causing deviations from linearity are cancelled out and mixtures display linear behaviour.

1 aBeniwal, Vijay1 aShukla, Shashi, K.1 aKumar, Anil uhttps://library.ncl.res.in/content/deviation-polarity-linearity-liquid-mixtures-containing-ionic-liquid-002303nas a2200157 4500008004100000022001400041245011500055210006900170260007100239300001400310490000800324520164600332100002501978700001602003856012602019 2015 eng d a1520-610600aDissociation of equimolar mixtures of aqueous carboxylic acids in ionic liquids: role of specific interactions0 aDissociation of equimolar mixtures of aqueous carboxylic acids i a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcAPR a5537-55450 v1193 a

Hammett acidity function observes the effect of protonation/deprotonation on the optical density/absorbance of spectrophotometric indicator. In this work, the Hammett acidity, H-0, of equirriolar mixtures of aqueous HCOQH, CH3COOH, and CH3CH2COOH was measured in 1-methylimidazolium-, 1-methylpyrrolidinium-, and 1-methylpiperidinium-based protic ionic liquids (PILs) and 1-buty1-3-methylimidazolium-based aprotic ionic liquid (AIL), with formate (HCOO-) anion. Higher H-0 values were observed for the equimolar mixtures of aqueous carboxylic acids in protic ionic liquids compared with those of the aprotic ionic liquid because of the involvement of the stronger specific interactions between the conjugate acid of ionic liquid and conjugate base of carboxylic acids as suggested by the hard soft acid base (HSAB) theory. The different Ho values for the equimolar mixtures of aqueous carboxylic acids in protic and aprotic ionic liquids were noted to depend on the activation energy of proton transfer (E-a,H(+)). The higher activation energy of proton transfer was obtained in AIL indicating lower ability to form specific interactions with solute than that of PILs. Thermodynamic parameters determined by the ``indicator overlapping method'' further confirmed the involvement of the secondary interactions in the dissociation of carboxylic acids. On the basis of the thermodynamic parameter values, the potential of different ionic liquids in the dissociation of carboxylic acids was observed to depend on the hydrogen bond donor acidity (alpha) and hydrogen bond acceptor basicity (beta), characteristics of specific interactions.

1 aShukla, Shashi, Kant1 aKumar, Anil uhttps://library.ncl.res.in/content/dissociation-equimolar-mixtures-aqueous-carboxylic-acids-ionic-liquids-role-specific-1