Polymers with triphenylamine units: Photonic and electroactive materials

Organic hole-transporting materials are intensively investigated as thin-layer electro-optical devices, including organic light-emitting diodes, solar cells, organic field-effect transistors and photo-refractive holographic materials. In this review, we discuss synthetic routes and optical (UV-vis, PL, CV) and electrical (I-V, EL, hole drift mobility) properties of polymers with triphenylamine (TPA) units in the main chain or as pendant groups, such as poly(vinylene)s, poly(amide)s, poly(imide)s, poly(azomethine)s, poly(arylate)s, poly(urethane)s and poly(ester)s. The introduction of vinyl, acetylene, ester, imide, amide or azomethine moieties in TPA leads to new functional materials based on their synergistic effects. The introduction of bulky triphenylamine in macromolecules tends to suppress intermolecular aggregation, reduce the crystallisation propensity and improve the hole-transporting ability of the materials.