02452nas a2200229 4500008004100000022001400041245012000055210006900175260006800244300001400312490000700326520157900333653001701912653002101929653003301950653002701983653002202010653003302032100001402065700001702079856012602096 2009 eng d a0887-624X00aSynthesis and self-organization properties of copolyurethanes based on perylenediimide and naphthalenediimide units0 aSynthesis and selforganization properties of copolyurethanes bas a111 RIVER ST, HOBOKEN, NJ 07030 USAbJOHN WILEY & SONS INCcFEB a1224-12350 v473 a

A series of perylene and naphthalene diimide-containing random copolyurethanes with different ratios of perylene/naphthalene diimide content was synthesized and characterized. Copolymerization improved the solubility of these rigid aromatic diimides, and the copolymers were soluble in common organic solvents like chloroform, tetrahydrofuran, and so forth. The absorption spectra of perylene-based copolymers showed a red-shifted peak at a wavelength of 557 nm corresponding to J-type aggregates. For naphthalene copolymers, the quenching of fluorescence at higher naphthalene incorporation suggested the presence of aggregates because of the extensive pi-pi stacking of the aromatic core. FTIR spectroscopic analysis showed that the hydrogen bonding tendency of the polymer decreased with increase in perylene/naphthalene incorporation. The fluorescence spectra of the perylene polymers were exactly a mirror image of the absorption spectra. The fluorescence spectra of the naphthalene polymers at higher naphthalene incorporation showed a red-shifted excimer like emission peak, which was assigned as static excimers based on their excitation spectra. These polymers could exhibit two types of secondary interaction modes, namely, hydrogen bonding (via urethane linkage) and pi-stacking (via aromatic perylene or naphthalene units) thus highlighting the importance of polymer design in inducing self-organization at both low and high incorporation of the rigid bisimide moieties. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polyrn Chem 47: 1224-1235, 2009

10afluorescence10ahydrogen bonding10anaphthalene diimide polymers10apolyurethane copolymer10aself-organization10astructure-property relations1 aJancy, B.1 aAsha, S., K. uhttps://library.ncl.res.in/content/synthesis-and-self-organization-properties-copolyurethanes-based-perylenediimide-and-002343nas a2200241 4500008004100000022001400041245010100055210006900156260007600225300001400301490000700315520144400322653002001766653001501786653001101801653001801812653003301830653005601863100002001919700001901939700001701958856012601975 2011 eng d a0887-624X00aCorrelation of architecture with excimer emission in 100% pyrene-labeled self-assembled polymers0 aCorrelation of architecture with excimer emission in 100 pyrenel aCOMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USAbWILEY-BLACKWELLcAPR a1678-16900 v493 a

Pyrene was incorporated as pendant unit to side-chain urethane methacrylate polymers having a short ethyleneoxy or a long polyethyleneoxy spacer segment. The short-spacer pyrene urethane methacrylate was also incorporated either as block or random copolymer (1:9) along with polystyrene. The excimer emission was observed to be different for different polymers with the random copolymer exhibiting the lowest efficiency. But, the total quantum yield was highest (phi = 0.58) for random copolymer due to the high emission coefficient of monomer compared to that of excimer. The polymer dynamics were compared by steady state emission and fluorescence decay in THF or THF/water (9:1) solvent mixture and films. The solid state decay profile showed decay without a rise time indicating presence of ground state aggregates. In THF/water (9:1), the decay profile at the excimer emission (500 nm) showed a rise time indicating dynamic excimers. The evolution of excimeric emission centred similar to 430 or similar to 480 nm as a function of temperature was also studied in THF/water (9:1). The I(E)/I(M) ratio for the lambda(343) nm excitation exhibited steady increase with temperature with the block copolymer PS-b-PIHP exhibiting the highest ratio and highest rate of increase; whereas, the random copolymer PS-r-PIHP had the lowest I(E)/I(M) ratios. (C) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 1678-1690, 2011

10aI(E)/I(M) ratio10aMorphology10apyrene10aSelf-assembly10astructure-property relations10atime-resolved and variable temperature fluorescence1 aKaushlendra, K.1 aDeepak, V., D.1 aAsha, S., K. uhttps://library.ncl.res.in/content/correlation-architecture-excimer-emission-100-pyrene-labeled-self-assembled-polymers-002444nas a2200265 4500008004100000022001400041245015200055210006900207260006700276300001400343490000700357520143400364653001901798653002901817653000901846653002101855653001801876653003301894653003201927653003001959100001501989700002802004700001702032856012902049 2016 eng d a0887-624X00aP4VP and oligo(phenylenevinylene)-perylenebisimide mixed donor-acceptor supramolecular comb polymer complexes with improved charge carrier mobility0 aP4VP and oligophenylenevinyleneperylenebisimide mixed donoraccep a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcAUG a2403-24120 v543 a

Random donor-acceptor (D-A) supramolecular comb polymers were formed when hydroxyl functionalized donor and acceptor small molecules based on Oligo(phenylenevinylene) (named OPVCN-OH) and Perylenebisimide (named UPBI-PDP), respectively, were complexed with Poly(4-vinyl pyridine) (P4VP). A series of random D-A supramolecular comb polymers were formed by varying the ratios of UPBI-PDP and OPVCN-OH with P4VP. A 100% P4VP-donor polymer complex [P4VP(OPV1.00)] and a 100% P4VP-acceptor polymer complex [P4VP(UPBI1.00)] were also synthesized and characterized. Complex formation was confirmed by FT-IR and H-1 NMR spectroscopy. Solid state structural studies carried out using small angle X-ray scattering and wide angle X-ray diffraction experiments revealed altered packing of the D and A molecules in the complexes. Transmission electron microscopy images showed lamellar structures in the <10 nm scale for the P4VP(OPV1.00), P4VP(UPBI1.00), and mixed P4VP (D-A) complexes. The effect of the nanoscopic D-A self-assembly on the bulk mobility of the materials was probed using SCLC measurements. The mixed D-A random complexes exhibited ambipolar charge transport characteristics with higher values for the average bulk hole mobility estimate. P4VP(OPV0.25+UPBI0.75) exhibited an average hole mobility in the order of 10(-2) cm(2) V-1 s(-1) and electron mobility 10(-5) cm(2) V-1 s(-1). (C) 2016 Wiley Periodicals, Inc.

10adonor-acceptor10aoligo(phenylenevinylene)10aP4VP10aPerylenebisimide10aSelf-assembly10astructure-property relations10asupramolecular comb polymer10asupramolecular structures1 aSaibal, B.1 aChithiravel, Sundaresan1 aAsha, S., K. uhttps://library.ncl.res.in/content/p4vp-and-oligophenylenevinylene-perylenebisimide-mixed-donor-acceptor-supramolecular-comb