Characteristics of Cyclic Triarylamine Hexamers and Application to Organic Field Effect Transistor

Cyclic hexamers consisting of a 4-octyl, 4-octyloxy and 4-(2-ethylhexyloxy)triphenylamine unit were synthesized via Buchwald-Hartwig cross coupling reaction using A-A, B-B type monomers in order to avoid the formation other cyclic oligomers such as pentamer heptamer. Unlike different size oligomers, all we examined showed clear cold crystallization 165-240°C DSC thermograms. Resulting characterized applied hole transporting active layer an organic field effect transistor. The hexamer with 4-octyl groups exhibited highest mobility (1.99 ×10-3 cm2 V-1s-1).