Photoluminescent and Electrochemical Properties of Novel Poly(aryl ether)s with Isolated Hole-Transporting Carbazole and Electron-Transporting 1,3,4-Oxadiazole Fluorophores

Abstract

Four novel poly(aryl ether)s consisting of alternate isolated hole-transporting carbazole and electron-transporting 1,3,4-oxadiazole segments were synthesized from the nucleophilic displacement reaction of bis(fluoride) monomers with bis(phenol) monomers. These poly(aryl ether)s are soluble in common organic solvents and exhibit good thermal stability with 5% weight loss temperature above 400 °C under a nitrogen atmosphere. The photoluminescent (PL) spectra and quantum yields of these polymers are dependent on the composition of the two isolated fluorophores. The formation of exciplex in P3 was observed in the film and solution state and resulted in the lower quantum yield. The quantum yields of P4 in solutions can increase from 0.04 of P3 to 0.36, due to the dilute effect, by introducing the inert bisphenol A segments. However, the PL spectra of P4 only showed a little blue shift in the film state. This means the interchain exciplex still dominated the emission of polymeric films. The HOMO and LUMO energy levels of these polymers have been measured from cyclic voltammetry. All the observations directly proved that the oxidation in polymers started at the hole-transporting segments. Both the electron and hole affinities of these polymers could be enhanced simultaneously due to the introduction of isolated hole-transporting carbazole and electron-transporting 1,3,4-oxadiazole segments.

Luminescent poly(p-phenylenevinylene) with 4-methylcoumarin side groups: Synthesis, optical properties and photo-crosslinking behaviors

“…. HOPPV is the model polymer corresponding to emitting backbone of COUPPV, whereas MC is corresponding to 7-oxy-4-methylcoumarin chromophores in side chain [16]. Emitting HOPPV shows maximal PL peak at 511, but electron-transporting models MC exhibits a band peaking at 380 nm.…”

A Fluorescent Chemosensor for Transition‐Metal Ions Based on Optically Active Polybinaphthyl and 2,2′‐Bipyridine

“…Herein, 5,5 0 -divinyl-2,2 0 -bipyridine, as a conjugated molecular linker unit and recognition binding site of the fluorescent chemosensor was introduced into the mainchain backbone of chiral polybinaphthyls to maintain conjugation between bipyridine and naphthyl segments so that the electron-transporting properties of the polymer may be improved and the electron density may shift away via the vinylene bridge, which could also increase the stability of the resulting chiral polymer. [25,[37][38][39][40][41][42] This kind of chiral conjugated polymer has a strong green-blue fluorescence. Moreover, this neutral ligand bipyridine can directly coordinate with different transition-metal ions to form polymer complexes.…”

Spatial Extent of the Singlet and Triplet Excitons in Luminescent Angular‐Shaped Transition‐Metal Diynes and Polyynes Comprising Non‐π‐Conjugated Group 16 Main Group Elements

“…In contrast to the body of work on luminescent metallaynes with the p-electron conjugated unit, there are no reports of similar systems possessing Group 16 chalcogen units in the backbone. There are also numerous reports on the syntheses and applications of purely organic polymeric systems of arylene ether, sulfide, sulfoxide and sulfone in the literature, [27][28][29][30] but little research on rigid-rod chalcogen-derived metallaynes and their corresponding polyynes has been carried out. To get a deeper insight, it is important to develop synthetic strategies leading to novel conjugated polymers with non-p-conjugated Group 16 heteroatoms in the polymer chains.…”