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Graphene flakes covalently modified with a conjugated polymer, poly[(9,9-dihexylfluorene)-co-alt-(9,9-bis-(6-azidohexyl)fluorene)] (PFA), were efficiently synthesised by a Cu-catalysed Huisgen 1,3-dipolar cycloaddition between alkyne-modified graphene and an azide-functionalised polymer. Two approaches for the modification of graphene with alkyne groups were investigated (coupling with a diazonium salt generated in situ or an amidation reaction) and the optimum conditions determined. The success of the click-coupling approach was confirmed by FTIR, (1)H NMR, Raman, and X-ray photoelectron spectroscopy (XPS). The absorption and emission spectra of the click product show a strong solvent dependency., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The presence of amplified spontaneous emission (ASE) by optical pump in polystyrene films doped with N,N'-di(10-nonadecyl)perylene-3,4:9,10-tetracarboxylic diimide (PDI-N) in a range of PDI-N concentrations between 0.25 and 5 wt. % is reported. Gain coefficients up to 10 cm(-1), at a pump intensity of 74 kW/cm2, were obtained. The lowest thresholds (approximately 15 kW/cm2) and largest photostabilities measured at 50% (approximately 50 min, i.e., 30,000 pump pulses) were obtained for concentrations up to 1 wt. %. The observation of an increase in the ASE threshold and a decrease in the photostability for larger concentrations is attributed to the presence of aggregated species.

[structure: see text] Novel suitably functionalized tetracyanoanthraquinodimethane (TCAQ) derivatives covalently linked to thiophene moieties have been synthesized. The thiophene-based monomers have been chemically polymerized and copolymerized to yield new and soluble donor-acceptor double-cable polymers. The absorption and emission data reveal that the optical properties can be finely tuned by modifying the ratio of monomers in the copolymerization process.

Abstract: The first main-chain copolymer containing TCAQ and enantiomerically pure binaphthyl moieties connected at 2,6 positions of the TCAQ ring was successfully synthesized by means of a polycondensation reaction. Cyclic voltammetry investigations show that TCAQ preserves its acceptor ability in the polymer system and preliminary photophysical investigations show fluorescence quenching in mixtures containing the acceptor polymer and fluorescent conjugated polymers. [Copyright &y& Elsevier]

This article presents a study on the exceptionally small attenuation factors in molecular wires. The potential of molecular-sized materials for electronic and photonic applications has led to an ever increasing interest in developing and probing molecular-scale wires) &b.pie;-Conjugated oligomers, such as oligo p-phenylenevinylenes, oligo-PPVs, are among those molecules which act as efficient molecular wires. Only a few reports on electron transfer through the &b.pie;-conjugated chains of oligo-PPVs are known. In this light, the importance of energy matching between the donor and bridge components, for achieving molecular-wire behavior, has been highlighted.

Abstract: A general synthetic strategy toward unsymmetrical hexaazatriphenylene (HAT) derivatives has been developed. The versatility of the strategy is used to synthesize a family of ambipolar donor–acceptor–donor (D–A–D) chromophores, which exhibit broad intramolecular charge transfer (ICT) bands in their solution UV–vis spectra. [Copyright &y& Elsevier]

In this communication, a novel two-dimensional polymer network (DAPT-TFP) has been synthesized based on pyrenetetraone moieties connected through robust enamine functional groups. Results show that DAPT-TFP exhibit high thermal and chemical stability, even after subjecting the material to a basic or acidic media for certain time (1 M H 2 SO 4 or 1 M NaOH, respectively). An application to conductive additive-free electrode is detailed, as a proof of the ideal interaction between the ions of the neutral aqueous electrolyte and the molecular polymer nanostructure activated by simple acidic treatment. Thus, the study indicates that the redox properties of new organic electrode materials exhibiting limited electroactive properties can be boosted by a straightforward acidic treatment. Image 1 • A novel 2D polymer network was synthesized based on pyrenetetraone moieties linked by enamine groups. • The polymer shows reversible redox activity in neutral aqueous media after acidic activation without any conductive additives. • This strategy envies novel possibilities of developing materials by applying low-cost methods. [ABSTRACT FROM AUTHOR]