02417nas a2200229 4500008004100000022001400041245013400055210006900189260006800258300001400326490000700340520153300347653002401880653001701904653003001921653002401951653003601975100001402011700002002025700001902045856012302064 2009 eng d a0887-624X00aControl of molecular aggregation in symmetrically substituted pi-conjugated bulky poly(p-phenylenevinylene)s and their copolymers0 aControl of molecular aggregation in symmetrically substituted pi a111 RIVER ST, HOBOKEN, NJ 07030 USAbJOHN WILEY & SONS INCcMAY a2631-26460 v473 a

A new series of symmetrically substituted bulky PPV-copolymers based on poly(bis-2,5-(2-ethylhexyloxy)-1,4-phenylenevinylene) (BEH-PPV) bearing tricyclodecane (TCD) pendants were synthesized to study the effect of chain aggregation in the pi-conjugated polymer backbone. The composition of the copolymers was varied up to 100 mol % and the structures of the copolymer were confirmed by NMR and FTIR. The molecular weights of the copolymers were obtained as M(w) = 11,500-1,78,800 depending on the TCD-incorporation in BEH-PPV. The origin of the pi-aggregation was investigated using mixture of solvents (polar or nonpolar) or temperature as external stimuli. Absorption, photoluminescence, and time-resolved fluorescence decay techniques were employed as tools to trace molecular aggregation in solution and solid state. The TCD-substituted bulky copolymers showed almost twice the enhancement in photoluminescence compared with that of BEH-PPV Solvent-induced aggregation studies of copolymers revealed the existence of strong molecular aggregation in BEH-PPV compared with that of bulky copolymers. Variable temperature studies further evidence for the reversibility of molecular aggregation on beating/cooling cycles and showed isosbetic points with respect to free and aggregated polymer chains. Time-resolved fluorescent studies confirmed the existence of free and aggregated pi-conjugated species with a life time of 0.1 to 1.0 ns. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2631-2646, 2009

10aconjugated polymers10afluorescence10apoly(p-phenylenevinylene)10asolution properties10aStructure-property relationship1 aResmi, R.1 aAmrutha, S., R.1 aJayakannan, M. uhttps://library.ncl.res.in/content/control-molecular-aggregation-symmetrically-substituted-pi-conjugated-bulky-polyp-002423nas a2200253 4500008004100000022001400041245010700055210006900162260010600231300001200337490000700349520146400356653001401820653001001834653002501844653001401869653003601883100002901919700003001948700002301978700002802001700002702029856011302056 2010 eng d a0014-305700aSynthesis and characterization of new aromatic polyesters containing cardo decahydronaphthalene groups0 aSynthesis and characterization of new aromatic polyesters contai aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcAPR a709-7180 v463 a

Three cardo bisphenols containing decahydronaphthalene group viz., 4,4'-(octahydro-2(1H)-naphthylidene)bisphenol, 4,4'-(octahydro-2(1H)-naphthylidene)bis-3-methylphenol and 4,4'-(octahydro-2(1H)-naphthylidene)bis-3,5-dimethylphenol were synthesized starting from commercially available 2-naphthol and were utilized for synthesis of new aromatic polyesters by phase transfer-catalyzed interfacial polycondensation with isophthaloyl chloride, terephthaloyl chloride and a mixture of isophthaloyl chloride and terephthaloyl chloride (50:50 mol %). Inherent viscosities and number average molecular weights (M(n)) of polyesters were in the range 0.35-0.84 dL/g and 13300-48,500 (Gel Permeation Chromatography, polystyrene standard), respectively. Polyesters were readily soluble in organic solvents such as dichloromethane, chloroform, tetrahydrofuran, meta-cresol, pyridine, N,N-dimethylformamide, N,N-dimethylacetamide, and 1-methy1-2-pyrrolidinone at room temperature and could be cast into tough, transparent and flexible films from their chloroform solutions. Wide-angle X-ray diffraction measurements revealed the amorphous nature of polyesters. The glass transition temperature of polyesters was in the range 207-287 degrees C. The temperature at 10% weight loss (T(10)), determined from thermogravimetric analysis of polyesters, was in the range 425-460 degrees C indicating their good thermal stability. (C) 2010 Elsevier Ltd. All rights reserved.

10abisphenol10aCardo10aDecahydronaphthalene10apolyester10aStructure-property relationship1 aHonkhambe, Pandurang, N.1 aBhairamadgi, Nagendra, S.1 aBiyani, Mahesh, V.1 aWadgaonkar, Prakash, P.1 aSalunkhe, Manikrao, M. uhttps://library.ncl.res.in/content/synthesis-and-characterization-new-aromatic-polyesters-containing-cardo-001760nas a2200217 4500008004100000022001400041245006500055210006500120260007500185300001200260490000700272520100800279653001601287653001501303653002701318653003601345100001801381700002101399700002601420856009601446 2015 eng d a1566-254300aStudies on melt processable biocomposites of polylactic acid0 aStudies on melt processable biocomposites of polylactic acid a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGER/PLENUM PUBLISHERScSEP a321-3330 v233 a

Melt processable microcrystalline cellulose (MCC)/poly(lactic acid) (PLA) composites were successfully prepared by twin-screw extrusion. Several characterization techniques were used to investigate the effect of MCC on rheological behavior, morphology, crystallization and melting behavior of the PLA and structure-property correlation of the MCC/PLA composites has been established. Rheological measurements showed that the addition of MCC has a dramatic influence on the low frequency relaxations of PLA chains and above 5 % of MCC, it forms percolated network structure. Differential scanning calorimeter analysis showed that MCC acted as nucleating agent enhancing crystallization below the percolation concentration. Properties of MCC/PLA composites have been compared with that of talc and CaCO3 filled composites. Talc is found to be more effective in crystallizing PLA than MCC and CaCO3. MCC/PLA composites are found be melt processable like that of talc and CaCO3 filled PLA composites.

10aBiopolymers10acomposites10aRheological properties10aStructure-property relationship1 aJoseph, Seena1 aDeenadayalan, E.1 aMahanwar, Prakash, A. uhttps://library.ncl.res.in/content/studies-melt-processable-biocomposites-polylactic-acid-0