Synthesis and photophysical study of new blue fluorescent poly(azomethine-1,3,4-oxadiazole)s containing dimethylamino groups

Abstract

New aromatic polyazomethines were synthesized by polycondensation reaction of a diamine containing 1,3,4-oxadiazole ring, namely, 4,4′-diamino-4″-[2-(4-phenoxy)-5-(4-dimethylaminophenyl)-1,3,4-oxadiazole)]triphenylmethane, with terephthalic aldehyde or bis(4-formylphenoxyphenyl)fluorene, by using N-methyl-2-pyrrolidinone (NMP) as solvent. The polymers were easily soluble in polar solvents, such as NMP, N, N-dimethylacetamide, or chloroform, and showed high thermal stability with the initial decomposition temperature above 415°C and the temperature of 10% weight loss in the range of 450–460°C. They exhibited high char yield at 800°C in the range of 52–56%. Optical properties were studied by absorption and photoluminescence spectra. In solution, the polymers presented two absorption maxima in the ranges 273–278 and 330–346 nm and emitted violet-blue light in the range of 413–468 nm, depending on the solvent polarity. The Stokes shift and emission quantum yield values depend on the polymer structure and solvent polarity. The emission intensity in NMP solution was enhanced upon increasing the HCl concentration, while the absorption spectral profile was slightly influenced.

Synthesis, characterization, photophysical and surface properties of poly(amino naphthalene) and its poly(azomethine) compound

“…Conjugated poly(azomethine)s have used in the production of polymeric light emitting diodes (PLED) 7,8 and solar cells 9,10 . Also, they have showed fluorescence properties because of conjuge π‐bonding 11–13 . Furthermore, poly (azomethine)s have the ability to form a good film 14,15 for high‐quantum efficiency, light emitting, sensitivity to photonic and electronic stimuli, macromolecular interaction and multi‐color emission properties when excited at certain wavelengths 16–18 .…”

Flexible oligomeric silicon‐containing poly(ether‐azomethine)s obtained from epoxide derivatives. Synthesis and characterization

“…This strongly limits their characterization in solution and their applications in some fields, especially those in which the polymers should be coated for solid‐state applications. Several researchers have shown that an adequate monomer design can improve the solubility of these polymeric materials through specific functionalizations such as meta ‐substitutions on the aromatic rings, and the incorporation of side groups, aliphatic moieties, flexible links, asymmetrical monomers, and bulky substituents along the main chains . However, as the flexibility of the chains increased, the glass‐transition temperature ( T g ) of the material should decreased.…”

Microwave-Assisted Synthesis of an Alternant Poly(fluorene–oxadiazole). Synthesis, Properties, and White Light-Emitting Devices

“…In this line of thought, great findings were achieved by joining the electron donating fluorene with building blocks containing the electron withdrawing oxadiazole [13]. An overview of the literature data revealed that oxadiazole and fluorene-based chromophores were joined by a randomly [14,15,16] or alternately [17,18,19,20,21] manner by Suzuki or Still polycondensation, in various mixtures with other aromatic/heterocyclic moieties. Besides, polyfluorene with oxadiazole pendant units [22,23,24] or low molecular weight compounds [25,26,27] were also synthetized.…”