In this work, we report the synthesis, characterization, and application of two regioirregular naphthalenediimide (NDI)-based alternating conjugated polymers, namely P1 and P2, in which nitrile-substituted moiety, 2,3-bis(thiophen-2-yl)acrylonitrile and NDI moiety act as donor and acceptor unit, respectively. The two regioirregular polymers possess low-lying LUMO energy levels of -3.92 eV for P1 and -3.96 eV for P2. Both polymers possess typical dual-band UV-Vis-NIR absorption profiles of NDI-based polymers, and show broadened and red-shifted absorption spectra in the solid state compared with those in solutions. Field-effect transistor devices with top-gate bottom-contact configuration were used to evaluate the polymers' semiconducting properties. The two polymers exhibited promising and air-stable ambipolar charge transport characteristics. Thin film microstructure investigations (AFM and 2D-GIXRD) suggest both polymers formed continuous and smooth thin films, and adopted predominantly face-on molecular packing in the solid state. (c) 2017 Wiley Periodicals, Inc.