New electro-active oxetanyl-functionalized oligomers containing carbazol-3,6-diyl and different aromatic amino groups in the main chain

A series of new cross-linkable oligomers based on 9-(3-methyloxetan-3-ylmethyl)carbazol-3,6-diyl and different aromatic amino groups were synthesized through modified Ullmann coupling reactions. The resulting derivatives were characterized by gel permeation chromatography, differential scanning calorimetry and thermogravimetric analysis. These materials possess high thermal stability with onset decomposition temperatures of 351-384 °C. Their glass transition temperatures range from 154 to 250 °C. Layers of the oligomers exhibit low ionization potentials ranging from 5.05 to 5.15 eV as established by electron photoemission technique.