Synthesis and optical and electrochemical properties of novel polyethers containing isolated distyrylbenzene derivatives and side‐aromatic 1,3,4‐oxadiazole chromophores

Abstract

New polyethers (P2, P4) with isolated emitting distyrylbenzene derivatives and pendant aromatic 1,3,4-oxadiazole chromophores have been prepared by the Horner-Wadsworth-Emmons olefination reaction. Polyethers P1 and P3 without oxadiazole groups have also been synthesized for comparison. The reduced viscosities were about 0.20 -0.33 dL/g, and the solubility in organic solvents increased with a number of side methoxy or ethoxy substituents in the distyrylbenzene section. Absorption spectra showed two peaks at 371-388 and 304 nm that corresponded to the -* transition of the conjugated distyrylbenzene derivatives and aromatic oxadiazoles, respectively. The band gaps were at 2.76 -2.85 eV, which were calculated from onset absorption in the film state. The photoluminescence (PL) maxima were at 459 -469 nm, indicating that they are blue-emitting materials, and the relative PL quantum efficiencies were 0.62-0.77 and 0.23-0.40 in solution and the film state, respectively. Cyclic voltammetric investigations demonstrated that oxadiazole moieties decrease the barrier of electron injection but also retard hole injection.

Synthesis and Optically Acid-Sensory and Electrochemical Properties of Novel Polyoxadiazole Derivatives

“…[11][12][13][14] The advantageous physical properties of oxadiazole-containing polymeric materials, coupled with their interesting photophysical features, have prompted studies concerned with the nature of their excited state. These planar polymeric materials have been shown to have closely packed π-conjugated structures capable of interchain excimer as well as charge-transfer complex (exciplex) formation.…”

Poly(phenylene vinylene)‐based copolymers containing 3,7‐phenothiazylene and 2,6‐pyridylene chromophores: Fluorescence sensors for acids, metal ions, and oxidation

“…The E values of the copolymers can be estimated from their onset absorption wavelength (UV onset ) 32. In the film state, the UV onset values of P1 – P3 are 439, 465, and 531 nm, respectively, and the corresponding E values are 2.83, 2.67, and 2.34 eV (Table 3).…”

Specific spectral characteristics of some phenylquinoxaline derivatives

“…Due to their optoelectronic properties, high thermal stability and good mechanical properties, poly(oxadiazole ether)s play an important role in materials science [7][8][9].…”