“…Recently, we have synthesized a new hyperbranched polymer (HB‐car), constructed fully by carbazole moieties, which exhibited enhanced hole‐transporting ability in comparison with the famous carbazole‐containing polymeric HTM, poly(vinylcarbazole) (PVK) 27. On the other hand, among the reported carbazole‐based polymers, there are nearly no polymers in which the C–N bonds are present in the main chain, unlike other type of polymers, such as PVK, poly‐(3,6‐carbazole)s, poly(2,7‐carbazole)s, etc 21, 24–30. Therefore, to further develop more carbazole‐based hyperbranched HTM with good properties, and explore alternative synthetic route in addition to the relatively difficult one used previously,27 in this paper, we conveniently prepared a new “AB 2 + A 2 + B 2 ”‐type HPU with good solubility and high molecular weight constructed by carbazole moieties through carbon–nitrogen bonds via the standard copper‐catalyzed Ullmann condensation reaction (Scheme ).…”