The copper catalyzed Ullmann polymerization is rarely used in polymer chemistry filed owing to the covered mechanism and insufficient conversion. Herein, we present the development of an efficient Ullmann C-N coupling polymerization route to synthesize conjugated Donor-Acceptor (D-A) polymers containing thiophene-phthalazinone moiety. The model reactions were carried out to investigate varies solvents, bases, catalytic systems and substrate reactivity effects on the Ullmann C-N coupling reactions. We demonstrate that the reaction conversion is highly depended on the substrate reactivity. By designing rational structures of thiophene-based di-bromo monomers, the molecular weights of polymers synthesized by classic Ullmann C-N coupling polymerization are high, in range of 6.4-34.6 kDa (PDI = 1.54-3.18) with 77-98% yields. Benefiting from the D-A conjugated effect of thiophene-phthalazinone moiety, the optoelectronics properties were studied and these nine polymers show strong UV-Vis-NIR absorption manners and emission color from blue to red regions. Overall, given the discussions and results in this work offer a new perspective for classic Ullmann C- N coupling polymerization to synthesize high molecular weight polymers as promising candidates for photoelectric materials. (C) 2016 Elsevier Ltd. All rights reserved.