Khalid Naila, Iqbal Asma, Siddiqi Humaira Masood, Park O Ok
Chemistry Department, Quaid-I-Azam University, Islamabad, 45320, Pakistan.
Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, South Korea.
J Fluoresc. 2017 Nov;27(6):2177-2186. doi: 10.1007/s10895-017-2157-4. Epub 2017 Aug 15.
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.
通过N-(4-氨基苯基)-N-(4-苯氧基苯基)苯-1,4-二胺（DA）与各种二醛合成了一系列聚甲亚胺（PAM），以研究聚合物链结构和基于三苯胺的苯氧基侧基对光电性能的影响。通过溶解度测试、凝胶渗透色谱法、粘度测量、傅里叶变换红外（FTIR）光谱和CHN元素分析对所得聚甲亚胺进行结构表征。通过紫外可见光谱、光致发光、时间相关光子计数光谱分析（TCSP）和循环伏安法研究材料的光物理和电化学性质。通过差示扫描量热法评估聚甲亚胺的热稳定性，热重分析表明其在高达300℃时稳定。这些聚合物表现出0.99至1.15 g dL的中等特性粘度范围和可观的有机溶剂溶解性。我们合成的材料中存在三苯胺和甲亚胺（CH=N）键，使其具有荧光性，在375nm激发下发射绿光，量子效率为3.9-8.5%。新型聚甲亚胺中对位的苯氧基侧基也降低了起始氧化电位并提高了HOMO能级。此外，共轭的存在增加了共轭聚合物中激发态的荧光时间，发现其在9.22-11.17 ns范围内，足以用于未来的光电应用。
