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<p>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</p>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-0