Synthesis and characterization of electron transporting polymers having thioxanthene derivatives

Acrylate and methacrylate type monomers containing thioxanthene derivative were synthesized and radically polymerized to yield electron transporting polymers. The obtained polymers are soluble in common solvents such as tetrahydrofuran (THF), chloroform, dimethylformamide (DMF). Cyclic voltammograms of all polymers showed two well-defined pairs of reduction and oxidation peaks indicating that polymers are electrochemically active. The polymers with dicyanomethylated thioxanthene derivative were more easily reduced than those with unmodified one because of the strong electron-withdrawing effect of dicyanomethyl groups, while the latter showed higher electron drift mobility than the former. Drift mobility was discussed in relation to the structure of the lowest unoccupied molecular orbital (LUMO) and the electron distribution. A well-balanced distribution of electrons plays an important role for a high-mobility material.