02176nas a2200253 4500008004100000022001400041245009300055210006900148260006700217300001400284490000800298520119700306653005201503653004401555653002301599653003001622653003701652653001401689100002801703700002401731700002301755700001901778856012501797 2006 eng d a0021-899500aSynthesis and characterization of cholesteric thermotropic liquid crystalline polyesters0 aSynthesis and characterization of cholesteric thermotropic liqui a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcJAN a1232-12370 v1033 a

Cholesteric liquid crystalline polyesters were successfully synthesized from isosorbide, methyl hydroquinone, and isophthaloyl chloride. Homo/copolyesters were synthesized by the solution polycondensation method, for which a mild organic base such as pyridine was employed. Inherent viscosities of polyesters P-3-P-5 were in the range of 0.31-0.39 dL/g at 25 degrees C in chloroform, and polyesters P-1 and P-2 were insoluble in chloroform. Homo/copolyesters based on isosorbide, methyl hydroquinone, and isophthalic acid had thermal stability at more than 300 degrees C on the basis of 10% weight loss. The thermotropic liquid crystalline properties were examined by differential scanning calorimetry and polarizing optical microscopy. Wide-angle X-ray diffraction study demonstrated that polyesters P-1, P-2, and P-3 were semicrystalline, whereas the degree of crystallinity of polyesters P-4 and P-5 was less than 5%. Copolyester P-4 showed formation of a yellow iridescent streak at 209 degrees C on heating and development of a Grand-jean texture at 270 degrees C on heating. These are typical textures of the cholesteric liquid crystalline phase. (c) 2006 Wiley Periodicals, Inc.

10acholesteric liquid crystalline polymers (ChLCP)10aDifferential scanning calorimetry (DSC)10aoptical microscopy10asolution polycondensation10aThermogravimetric analysis (TGA)10aviscosity1 aJadhav, Sushilkumar, A.1 aChougule, Rahul, R.1 aShinde, Yogesh, A.1 aChavan, Nayaku uhttps://library.ncl.res.in/content/synthesis-and-characterization-cholesteric-thermotropic-liquid-crystalline-polyesters02761nas a2200253 4500008004100000245011300041210006900154260000800223300001400231490000600245520182500251653001602076653001802092653003802110653002502148653003202173653002502205653004502230653003202275653001702307653003302324100001902357856013102376 2011 eng d00aSynthesis and characterization of cholesteric thermotropic liquid crystalline polyesters based on isosorbide0 aSynthesis and characterization of cholesteric thermotropic liqui cOCT a1520-15270 v23 a

Generally main chain cholesteric thermotropic liquid crystalline polymers are prepared form chiral dia-cid or diol monomer. But these monomers are costly. Isosorbide is chiral cycloaliphatic diol accessible from renewable resources in the form of pure enantiomers. Thus it is used to synthesize main chain cholesteric thermotropic liquid crystalline polymers. Incorporation of phenyl hydroquinone into the backbone of the main chain frustrates chain pack-ing, thus lowering the crystallinity and depressing the melting point below the degradation temperature, also improves the solubility due to disruption of packing and maintains the mechanical and thermal performance. Results: Optical microscopy study reveals that more than 50% of isosorbide content with phenyl hydroquinone and terephthalic acid showed “yellow iridescent oily streaks” with a background of mosaic/marble texture. These are the typical textures of cholesteric liquid crystalline phase. Copolyesters based on phenyl hydroquinone, isosorbide and terephthalic acid are soluble in aprotic solvents like N,N-dimethylacetamide (DMAC), dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), and N-methyl-2-pyrrolidone (NMP). Solubility increases with the content of isosorbide percent. Thermal stabil-ity of all copolyesters was more than 300˚C on the basis of 10 wt% loss. Conclusions: It was found that main chain cholesteric thermotropic liquid crystalline polymers can be prepared form chiral cycloaliphatic diol such as isosorbide. Main chain cholesteric thermotropic liquid crystalline polyesters are prepared from phenyl hydroquinone, isosorbide and terephthalic acid showed thermal stability more than 300˚C. Main chain cholesteric thermotropic liquid crystalline polymers are soluble in aprotic solvents like DMAC, DMSO, DMF and NMP

10aCholesteric10aCrystallinity10adifferential scanning calorimetry10aInherent Viscosity10aLiquid Crystalline Polymers10aOptical Microscopy10aSolubility and Solution Polycondensation10aThermo Gravimetric Analysis10athermotropic10aWide Angle X-Ray Diffraction1 aChavan, Nayaku uhttps://library.ncl.res.in/content/synthesis-and-characterization-cholesteric-thermotropic-liquid-crystalline-polyesters-based01725nas a2200241 4500008004100000022001400041245006600055210006600121260010300187300001200290490000700302520091100309653001001220653002801230653000901258653001201267653001101279653002201290100002901312700002301341700001901364856010001383 2014 eng d a0376-469900aSynthesis and characterization of azoxy based mesogenic diols0 aSynthesis and characterization of azoxy based mesogenic diols aANUSANDHAN BHAWAN, 2 RAFI MARG, NEW DELHI, 110001, INDIAbCOUNCIL SCIENTIFIC & INDUSTRIAL REScMAR a359-3620 v533 a

Azoxy based rigid mesogenic diols have been synthesized using two steps. Phenol/cresol is used as starting material. Synthesized diols are characterized by IR, H-1 and C-13 NMR, and mass spectroscopic methods. Thermal properties have been determined by thermo gravimetric analysis method and crystallinity patterns have been obtained by wide angle X-ray diffiactogram. Substituted phenol (methyl) is used to study the effect of substitution on physical and thermal properties of rigid azoxy mesogenic diol. The detailed characterization of azoxy based rigid diols is reported in this communication, which is highly useful for fundamental and applied research, particularly in liquid crystals and liquid crystalline polymers. The experimental results reveal that phenol based rigid mesogenic diols have high thermal stability and degree of crystallinity than methyl substituted rigid mesogenic diols.

10aAzoxy10adegree of crystallinity10adiol10amesogen10aphenol10athermal stability1 aMulani, Khudbudin, Baban1 aGanjave, Nitin, V.1 aChavan, Nayaku uhttps://library.ncl.res.in/content/synthesis-and-characterization-azoxy-based-mesogenic-diols-001768nas a2200229 4500008004100000022001400041245009600055210006900151260010600220300001000326490000700336520090900343653001401252653001501266653001701281653003001298653001901328100001701347700002501364700001901389856013001408 2014 eng d a0014-305700aSynthesis and characterization of hypercrosslinked hydroxyl functionalized co-polymer beads0 aSynthesis and characterization of hypercrosslinked hydroxyl func aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcOCT a46-580 v593 a

Hydroxyl functionalized beaded copolymers were synthesized from 2-hydroxy ethyl methacrylate by suspension polymerization using two different crosslinking agents (EDMA, DVB) and diluents (1,1,2,2-tetrachloroethane, 1,2-dichlorobenzene). Microporous beads with high surface area were successfully synthesized and characterized by different techniques. Maximum surface area obtained was 564 m(2)/g bearing uniform, spherical as well as non-aggregation images of beads. Thermal properties such as DTG and DSC reveal that, type of crosslinker (flexible/rigid) is major while its concentration is minor parameter that affect decomposition and softening temperature of copolymer. Swelling ratio of copolymer beads was examined as a function of crosslinker and crosslink density. Swelling behavior is in accordance with copolymer-solvent interaction parameter. (C) 2014 Elsevier Ltd. All rights reserved.

10aCopolymer10aMorphology10asurface area10aSuspension polymerization10aSwelling ratio1 aMane, Sachin1 aPonrathnam, Surendra1 aChavan, Nayaku uhttps://library.ncl.res.in/content/synthesis-and-characterization-hypercrosslinked-hydroxyl-functionalized-co-polymer-beads-002038nas a2200229 4500008004100000022001400041245012400055210006900179260010300248300001200351490000700363520112000370653002801490653002101518653002001539653002401559653002301583100002901606700002301635700001901658856013101677 2014 eng d a0376-469900aSynthesis and characterization of triad based rigid mesogenic diols derived from hydroquinone and 4-hydroxybenzoic acid0 aSynthesis and characterization of triad based rigid mesogenic di aANUSANDHAN BHAWAN, 2 RAFI MARG, NEW DELHI, 110001, INDIAbCOUNCIL SCIENTIFIC & INDUSTRIAL REScMAY a591-5960 v533 a

Triad based rigid mesogenic diols have been synthesized by four step synthesis method using protection-deprotection method. Hydroquinone and 4-hydroxy benzoic acid have been used as starting materials. Synthesized diols have been characterized by IR, H-1 and C-13 NMR, and mass spectroscopic methods. Thermal properties have been determined by thermo gravimetric analysis method and degree of crystallinity have been measured by wide angle X-ray technique. Substituted hydroquinones (methyl and chloro) have been used to study the effect of substitution on physical and thermal properties. Synthesis of rigid mesogenic diol monomer using p-hydroxy benzoic acid and hydroquinone is reported, which is a facile route. Hydrolysis of diacetate derivatives of rigid mesogenic diols is performed in good yields, even though two types of ester groups present in the same moiety, aromatic and aliphatic. The experimental results reveal that hydroquinone based rigid triad mesogenic diol have high thermal stability and degree of crystallinity as compared to methyl-and chloro-substituted rigid triad mesogenic diols.

10adegree of crystallinity10aester hydrolysis10aMesogenic diols10aspectral properties10aThermal properties1 aMulani, Khudbudin, Baban1 aGanjave, Nitin, V.1 aChavan, Nayaku uhttps://library.ncl.res.in/content/synthesis-and-characterization-triad-based-rigid-mesogenic-diols-derived-hydroquinone-and-001860nas a2200241 4500008004100000022001400041245008100055210006900136260010200205300001400307490000700321520098000328653001201308653003101320653001201351653003201363653002901395100001701424700001801441700002501459700001901484856011501503 2015 eng d a0250-470700aSynthesis and characterization of thermotropic liquid crystalline polyimides0 aSynthesis and characterization of thermotropic liquid crystallin aC V RAMAN AVENUE, SADASHIVANAGAR, P B \#8005, BANGALORE 560 080, INDIAbINDIAN ACAD SCIENCEScOCT a1553-15590 v383 a

Non-symmetrical and linear dyad-based mesogens were synthesised containing imine or ester bridging group. In the present work, due to the absence of branching in diamine-based mesogen, the structure has-rigidity inversely imine/ester bridging groups between two benzene rings imparts-flexible property to the mesogen and consequently rigid-flexible property has been balanced. The synthesised mesogens were characterized by different techniques including nuclear magnetic resonance and Fourier transform infrared spectroscopy. Liquid crystalline polymers (LCPs) were synthesised using pyromellitic dianhydride and 4-[(4-aminobenzylidene)amino]aniline or 4-aminophenyl-4-aminobenzoate. Subsequently, thermotropic liquid crystalline polymers (TLCPs) have also been evaluated to obtain optical microscopy textures at different temperatures which demonstrated interesting and notable changes. It is worth noting that marble-like textures were observed upto 200A degrees C.

10aDiamine10aliquid crystalline polymer10amesogen10aoptical microscopy textures10apyromellitic dianhydride1 aMane, Sachin1 aRajan, C., R.1 aPonrathnam, Surendra1 aChavan, Nayaku uhttps://library.ncl.res.in/content/synthesis-and-characterization-thermotropic-liquid-crystalline-polyimides-101797nas a2200241 4500008004100000022001400041245016500055210006900220260010000289300001200389490000600401520080400407653003201211653002601243653001901269653003001288653002301318100002701341700001801368700001901386700001901405856013101424 2015 eng d a1788-618X00aSynthesis of novel silica-polyimide nanocomposite films using aromatic-amino modified silica nanoparticles: mechanical, thermal and morphological investigations0 aSynthesis of novel silicapolyimide nanocomposite films using aro aDEPT POLYMER ENG, MUEGYETEM RKP 3, BUDAPEST, H-1111, HUNGARYbBUDAPEST UNIV TECHNOL & ECONcMAY a469-4790 v93 a

Silica nanoparticles were modified with aromatic amino groups and modified-silica/polyimide composite films were prepared using them. 3,3!, 4,4!-Benzophenone tetracarboxylic dianhydride (BTDA) and 4,4!-oxydianiline (ODA) were used as precursors for polyimide matrix. The structures of the modified nanoparticles and hybrid nanocomposites were identified using Fourier Transform Infrared (FTIR) spectrometry. The hybrid composite films were evaluated for mechanical, thermal and morphological characteristics. Morphological results describe a uniform dispersion of silica particles in the polymer matrix. The thermal stability and mechanical properties of polyimide composite were improved, and the decomposition temperature was increased when the amount of silica nanoparticles was increased.

10ahybrid polyimide composites10amechanical properties10aNanocomposites10ananoparticle modification10aThermal properties1 aGhorpade, Ravindra, V.1 aRajan, C., R.1 aChavan, Nayaku1 aPonrathnam, S. uhttps://library.ncl.res.in/content/synthesis-novel-silica-polyimide-nanocomposite-films-using-aromatic-amino-modified-silica-001927nas a2200229 4500008004100000022001400041245007200055210006900127260006700196300001000263490000800273520116600281653001501447653001501462653001701477653001301494653002701507100001701534700002501551700001901576856010201595 2016 eng d a0021-899500aSelective solid-phase extraction of metal for water decontamination0 aSelective solidphase extraction of metal for water decontaminati a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcJAN a428490 v1333 a

Metal-contaminated industrial effluent is a major concern for human health. Therefore, the removal of metal is of primary importance. In this study, metals were selectively extracted from water. Selective metal recovery was studied with a crown-ether-based polymer, wherein the selectivity was observed for strontium over lead. Parameters influencing the metal recovery, such as the contact time, adsorbent dosage, and metal-ion concentration, were evaluated. Interestingly, the adsorption rate of strontium was exponentially increased for the initial 4 h, and lead was adsorbed exponentially after 6 h. Notably, 98% strontium adsorption and 64% lead adsorption were obtained in 24 h. The Langmuir adsorption isotherm was in good agreement and demonstrated that the reactive sites of the adsorbent were homogeneous with monolayer metal adsorption with an adsorbent. The Freundlich adsorption isotherm was not obeyed by both metals. The pseudo-first-order and pseudo-second-order kinetics indicated that strontium was adsorbed by chemisorption and lead was adsorbed by physisorption. (c) 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 132, 42849.

10aAdsorption10acopolymers10acrosslinking10akinetics10aradical polymerization1 aMane, Sachin1 aPonrathnam, Surendra1 aChavan, Nayaku uhttps://library.ncl.res.in/content/selective-solid-phase-extraction-metal-water-decontamination-102137nas a2200229 4500008004100000022001400041245015800055210006900213260008700282300001000369490000700379520120700386653003701593653001401630653002901644100002701673700002401700700001801724700001901742700001901761856012701780 2016 eng d a0954-008300aSynthesis and characterization of thermally stable polyimides with a pendent phenothiazine unit based on new diamine 10-(3,5-diaminobenzoyl)phenothiazine0 aSynthesis and characterization of thermally stable polyimides wi a1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLANDbSAGE PUBLICATIONS LTDcFEB a26-330 v283 a

A novel diamine 10-(3,5-diaminobenzoyl)phenothiazine (DBPT) with a side chain containing phenothiazine unit was synthesized. A new family of polyimides (PIs) containing phenothiazine unit in the side chains has been successfully synthesized by direct polycondensation of DBPT with pyromellitic dianhydride, 3,3',4,4'-benzophenone tertacarboxylic dianhydride, and 4,4'-oxydiphthalic anhydride (ODA) via a conventional two-step chemical imidization process. The yield of polymers was good enough, which were soluble in most organic solvents. The molecular orbital energy gaps, thermal stability, and crystallinity of PIs were investigated by molecular modeling, thermogravimetric analysis, and wide-angle X-ray scattering, respectively. Thermal properties of polymers were good enough to permit the use of these PIs in various applications; only 49% weight loss is detected at 900 degrees C in nitrogen atmosphere. X-Ray diffraction clearly reveals the amorphous nature of PIs. A quantum modeling study (density functional theory) has shown the influence of dianhydride structure on the energy difference of highest occupied molecular orbital and lowest unoccupied molecular orbital energy levels.

10aphenothiazine-containing diamine10aPolyimide10athermally stable polymer1 aGhorpade, Ravindra, V.1 aThorave, Asmita, K.1 aRajan, C., R.1 aChavan, Nayaku1 aPonrathnam, S. uhttps://library.ncl.res.in/content/synthesis-and-characterization-thermally-stable-polyimides-pendent-phenothiazine-unit-001741nas a2200241 4500008004100000022001400041245017200055210006900227260008600296300001200382490000700394520074800401653003701149653002701186653002101213653002301234653002201257653002301279100002701302700002501329700001901354856012601373 2016 eng d a1060-132500aSynthesis of 2-phenoxy-2-phenylethyl acrylate and copolymerization with 2-phenylethyl acrylate: estimation of monomer reactivity ratios, thermal and optical properties0 aSynthesis of 2phenoxy2phenylethyl acrylate and copolymerization  a530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USAbTAYLOR & FRANCIS INCcMAY a457-4640 v533 a

A new aromatic based monomer 2-phenoxy-2-phenylethyl acrylate (PPEA) was synthesized. Copolymers of PPEA with 2-phenylethyl acrylate (PEA) were prepared by free radical polymerization. The reactivity ratios were estimated using various graphical methods. Structural parameters of the copolymers were obtained by calculating the dyad monomer sequence fractions and the mean sequence length. Optical properties of polymers such as refractive indices and UV-Visible absorption were investigated. The glass transition temperature and thermal degradation behavior of the copolymers were studied. Combined with the RI, transparency and thermal properties, prepared copolymers hold great promise as materials for intraocular lens applications.

10a2-Phenoxy-2-phenylethyl acrylate10a2-phenylethyl acrylate10acopolymerization10aOptical properties10areactivity ratios10aThermal properties1 aGhorpade, Ravindra, V.1 aPonrathnam, Surendra1 aChavan, Nayaku uhttps://library.ncl.res.in/content/synthesis-2-phenoxy-2-phenylethyl-acrylate-and-copolymerization-2-phenylethyl-acrylate