A new tetradodecyl-substituted DTBTBT donor unit is synthesized by a specific bis- annulation via Suzuki–Miyaura coupling and successfully incorporated into light absorbing electron donor copolymers for OPV and hole and electron transport OFET polymer devices. All copolymers (DTBTBT-co-benzothiadiazole (Bz), DTBTBT-co-thiophene (T) and DTBTBT- co-thienothiophene (TT)) show fully coplanar backbones and strong intermolecular ...