Synthesis and Photophysical Study of New Green Fluorescent TPA Based Poly(azomethine)s

Abstract

A series of poly(azomethine)s (PAMs) were synthesized from N-(4-aminophenyl)-N-(4-phenoxyphenyl)benzene-1,4-diamine (DA) and various dialdehydes to investigate the influence of structure of polymer chain and triphenylamine-based phenoxy pendant group on the optoelectronic properties. The structural characterization of the resulting poly(azomethine)s was carried out by solubility test, gel permeation chromatography, viscosity measurement, fourier transform infrared (FTIR) spectral and CHN elemental analysis. The photophysical and electrochemical properties of the materials were scrutinized by UV-vis, photoluminescence, time correlation photon counting spectral analysis (TCSP) and cyclic voltammetry. The thermal stability of the poly(azomethine)s was assessed by differential scanning calorimetry and thermogravimetric analysis found to be stable upto 300 °C. These polymers exhibit moderate inherent viscosity range from 0.99 to 1.15 g dL and appreciable organosolubility. The presence of triphenylamine and azomethine (CH = N) linkage in our synthesized materials rendered them fluorescent, emitting green light upon excitation at 375 nm with quantum efficiencies of 3.9-8.5%. The pendant phenoxy group at para-position in new poly(azomethine)s has also lowered the onset oxidation potentials and elevated the HOMO levels. Additionally, the presence of conjugation increases the fluorescence time of the excited state in conjugated polymers which was found in the range 9.22-11.17 ns, sufficient to be use in future optoelectronic applications.

Effect of Protonation on Optical and Electrochemical Properties of Thiophene–Phenylene-Based Schiff Bases with Alkoxy Side Groups

“…Azomethines (PAzs) are products of condensation (polycondensation) reaction between amines and aldehydes. Such reaction may proceed under mild conditions, using inorganic or organic catalysts or even without using any, as previously shown. , These types of materials were extensively studied due to their interesting thermal, electrical, and optical − properties and also due to the possible activity in some optoelectronic systems, such as bulk heterojunction photovoltaic cells, − perovskite solar cells, − organic light-emitting devices, , or electrochemical systems. , …”

Synthesis of Redox-Active, Fluorescent Triphenylamine Derivative for Detection of Heavy Metal Ions

“…3.04 (2H, t, J = 7.32 Hz, 6). 13 C-NMR (d 6 -DMSO) δ, ppm 157.9 (13), 152.8 (11), 144.7 (10), 138.8 (14), 137.9 (12), 129.1 (8), 129.9 (7)…”

“…These are credited to (π-π*) transition of the conjugated phenyl ring and (n-π*) transition of nitrogen and oxygen lone pair. The optical band gap (E g ), calculated from equation [11]:…”

Radical Copolymerization of N‐Vinylformamide with Methylvinylketone: An Approach to Iminium/Imine Ring Containing Polymers

“…studied an iminium ion end‐group‐functionalized polymer . Furthermore, there are many examples of linear poly(azomethines) reported, which can potentially react with electrophiles to iminium structures.…”