A Novel Azo‐Linked Polymer Bearing Trifluoromethyl Groups for I2 Capture

Abstract

AbstractIn this work, a novel three nitro‐group‐bearing monomer 3,6‐dinitro‐9‐(2‐trifluoromethyl‐4‐nitrophenyl)‐carbazole (Car‐3NO2‐CF3) via a CN coupling reaction between 3,6‐dinitro‐9H‐carbazole (Car‐2NO2) and 2‐chloro‐5‐nitrobenzotrifluoride is synthesized, and obtained single crystal and single crystal analysis data for this compound. The crystal system of Car‐3NO2‐CF3 is monoclinic and it has a P 21/c space group. This new monomer (Car‐3NO2‐CF3) is also utilized to synthesize a novel azo‐linked polymer (Azo‐Car‐CF3). The trifluoromethyl group has polar CF bonds, and thus it is an effective functional group for the capture of iodine. Azo‐Car‐CF3 has great thermal stability with a mass loss of only 10% at 414 °C, as well as good chemical stability as is demonstrated by its low solubility in common organic solvents such as tetrahydrofuran (THF), acetone, methanol, ethanol, and N,N‐dimethylformamide (DMF). The specific surface area of Azo‐Car‐CF3 can reach as high as 335 m2 g−1. Azo‐Car‐CF3 exhibits an excellent capacity for iodine adsorption and can reach up to 1198 mg g−1 in cyclohexane solution, and its adsorption capacity for iodine vapor can get to 2100 mg g−1. In addition, ethanol can be used to trigger the release of the captured iodine to be easily released from Azo‐Car‐CF3.