428865-56-9Relevant articles and documents
Design and synthesis of solution processable green fluorescent D-π-A dyads for OLED applications
Thurakkal, Shameel,Sanju, Krishnankutty S.,Soman, Anjaly,Unni, K. N. Narayanan,Joseph, Joshy,Ramaiah, Danaboyina
, p. 5456 - 5464 (2018)
New solution processable organic donor-π-acceptor dyads 1 and 2 having electron donating phenoxazine and electron accepting oxadiazole groups have been synthesized. Intramolecular electron communication between the donor and acceptor moieties of these dyads was tuned through changing the substitution pattern at the phenylene linker. The photophysical properties of these dyads have been studied in the solution and film states. These dyads showed green fluorescence and exhibited a positive solvatochromism in the emission spectra, which indicates more polar excited states owing to an efficient charge migration from the donor phenoxazine to the acceptor oxadiazole moiety. The electrochemical, morphological and thermal properties were investigated through cyclic voltammetry, thermogravimetric and atomic force microscopy (AFM) analyses. To understand the electronic structure and band gap of these dyads, density functional theory (DFT) calculations have been performed. Furthermore, we have fabricated the solution processed un-doped electroluminescence devices based on these dyads, which exhibited efficient green emission with Commission Internationale de l'Eclairage (CIE) coordinates of (0.26, 0.49) and (0.27, 0.47) for 1 and 2, respectively, with a luminance maximum of ca. 1751 cd m-2 for the dyad 1, thereby demonstrating its use in organic light emitting diodes (OLEDS).
Synthesis and characterization of alternating copolymers of fluorene and oxadiazole
Ding, Jianfu,Day, Michael,Robertson, Gilles,Roovers, Jacques
, p. 3474 - 3483 (2007/10/03)
Alternating copolymers of 9,9-dioctylfluorene and oxadiazole have been prepared by the tetrazole route or the Suzuki coupling reaction. In the polymers the oxadiazole units were evenly dispersed in the main chain at every one, P(F1-alt-Ox), three, P(F3-alt-Ox), or four, P(F4-alt-Ox), fluorene units. Another copolymer with an asymmetric repeat unit structure, P(F3-Ox-F1-Ox) has also been prepared for comparison. In this study, the tetrazole route has been demonstrated to offer several advantages for preparing polyoxadiazole with well-defined structures compared to other oxadiazole ring formation reactions. These advantages include: clean and fast reactions, mild reaction conditions, high yields, and high molecular masses of product. The glass transition temperature of copolymers ranged from 98 to 150 °C, and the copolymers show high thermal stability with decomposition temperatures around 430 °C. The UV-vis absorption and photoluminescence properties of all the copolymers in solutions are similar to those of poly(9,9-dioctylfluorene). All copolymers fluoresce in the blue-light range with quantum yields of ～70% in CH2Cl2 solution.
