Mejed Chemli

Synthesis, characterization and optical properties of distyrylanthracene-based polymers

Distyryl- and nitrodistyrylanthracene-based polymers (P1 and P2, respectively) have been synthesized and characterized. The polymers are fully soluble in common organic solvents and have number-average molecular weights of 18 570 and 23 480 g mol−1 for P1 and P2, respectively. The optical properties of the polymers were investigated by UV-visible absorption and photoluminescence spectroscopies. The optical gaps were estimated from the absorption-onsets of the polymer films; their values were 2.79, 2.75 eV for P1 and P2, respectively. A blue photoluminescence was observed in dilute solution. In solid thin film, Π–Π interactions influence the optical properties, and red-shifted photoluminescence spectra were obtained; a green emission (573 nm) for P1 and an orange one (605 nm) for P2 were observed. The HOMO and LUMO levels were estimated using cyclic voltammetry analysis. Single-layer devices of the indium-tin oxide/polymer/aluminum configuration were fabricated and showed relatively low turn-on voltages (5.14 V for P1 and 5.00 V for P2).

New Semiconducting Poly(arylene sulfide)s: Synthesis, Characterization, and Optical Properties

New semiconducting soluble poly(arylene sulfide)s were synthesized by Wittig polycondensation. The arylene moieties consist of distyrylbiphenyl (P1) and distyrylbithiophene (P2) π-conjugated systems. The polymers are fully amorphous and show good thermal stability. The absorption and photoluminescence properties of the polymers were investigated. P1 film has an optical gap of 2.95 eV and exhibits green-blue fluorescence. P2 shows a longer effective conjugation length with a gap of 2.42 eV and emits in the orange region. The HOMO/LUMO energy levels were estimated by cyclic voltammetry measurements. Single-layer diodes were fabricated and show relatively low turn-on voltages.