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

Macromol Rapid Commun. 2023 May;44(10):e2200982. doi: 10.1002/marc.202200982. Epub 2023 Apr 6.

Abstract

In 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 .

Keywords: azo-linkages; iodine captures; polymers; single crystals; trifluoromethyl groups.

MeSH terms

  • Ethanol
  • Hydrocarbons, Fluorinated / chemistry
  • Iodine*
  • Polymers*
  • Solvents

Substances

  • Polymers
  • Hydrocarbons, Fluorinated
  • Solvents
  • Iodine
  • Ethanol