3,3′-Bicarbazolyl-Containing Oxirane and its Reaction Products as New Glass-Forming Electroactive Materials

Abstract

Low-molar-mass oxiranyl-substituted 3,3′-bicarbazolyl derivatives were synthesized by the reaction of 3,3′-bicarbazolyl-containing oxirane with dimercapto compounds as linking agents. The cationic ring opening polymerization of oxirane monomers was performed using ytterbium (III) trifluoromethanesulfonate [Yb(OTf)₃] as a cationic initiator to obtain polyether. The full characterization of the compounds by mass spectrometry, IR, ¹H NMR, and ¹³C NMR is presented. All the compounds represent amorphous materials with glass transition temperatures ranging from 28°C to 112°C and with 5%-weight-loss temperatures exceeding 308°C. The electron photoemission spectra of the materials were recorded, and the ionization potentials of ca. 5.5 eV were established. Time-of-flight hole drift mobilities of the amorphous films of some synthesized compounds exceed 10⁻⁵ cm²/Vs at high electric fields.

Keywords:

• bicarbazolyl
• glass transition
• hole drift mobility
• ionization potential
• oxiranyl

Acknowledgments

Financial support of this research by the Lithuanian State Science and Studies Foundation is gratefully acknowledged. Habil. Dr. V. Gaidelis from the Department of Solid State Electronics, Vilnius University is thanked for the data of ionization potential measurements.

Notes

^a Determined by DSC during the 1st and the 2nd heating, scan rate 20°C/min, N₂ atmosphere.

^b The 5% weight loss temperature determined by TGA, heating rate 20°C/min, N₂ atmosphere.

^a λ = 310 nm.