Zoromba M Sh
Chemical and Materials Engineering Department, King Abdulaziz University, Rabigh 21911, Saudi Arabia; Chemistry Department, Faculty of Science, Port Said University, Port Said 42521, Egypt.
Spectrochim Acta A Mol Biomol Spectrosc. 2017 Dec 5;187:61-67. doi: 10.1016/j.saa.2017.06.028. Epub 2017 Jun 22.
A new (p-toluidine) oligomer (PTO) was facile synthesized and economically routed via chemical oxidative polymerization by potassium dichromate as an initiator in an acidic aqueous medium at room temperature. The characterization of (p-toluidine) oligomer (PTO) has been described by various techniques including Fourier transform infra-red (FTIR), UV-Visible measurements, Mass spectra, H NMR, and thermal gravimetric analysis (TGA). Solvatochromism of PTO was studied in different polaritiy solvents such as acetic acid, acetone, dimethyl formamide, ethanol, isopropanol, chloroform, p-xylene, dichloromethane and carbon teterachloride. The absorption bands were bathochromically shifted with increased polarity of the solvent (positive solvatochromism). PTO shows three isosbestic points at 333, 388 and 472nm in a binary mixture of acetone and chloroform. The deprotonation constants of PTO were found to be 3.1 and 5.8, based on spectrophotometric calculations. PTO was successfully used as an acid-base indicator; the acid solution color sharply turned from pink (acidic medium) to yellow (basic medium) at the end point.
一种新型的（对甲苯胺）低聚物（PTO）在室温下于酸性水介质中，以重铬酸钾作为引发剂，通过化学氧化聚合反应简便合成且成本低廉。（对甲苯胺）低聚物（PTO）的表征已通过多种技术进行描述，包括傅里叶变换红外光谱（FTIR）、紫外可见光谱测量、质谱、核磁共振氢谱（H NMR）以及热重分析（TGA）。在不同极性的溶剂如乙酸、丙酮、二甲基甲酰胺、乙醇、异丙醇、氯仿、对二甲苯、二氯甲烷和四氯化碳中研究了PTO的溶剂化显色现象。随着溶剂极性增加，吸收带发生红移（正溶剂化显色）。在丙酮和氯仿的二元混合物中，PTO在333、388和472nm处显示出三个等吸收点。基于分光光度法计算，发现PTO的去质子化常数分别为3.1和5.8。PTO成功用作酸碱指示剂；在终点时，酸溶液颜色从粉红色（酸性介质）急剧变为黄色（碱性介质）。
