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We report the synthesis of two noveldonor–acceptor copolymerspoly{[N, N′-bis(alkyl)-1,4,5,8-naphthalenediimide-2,6-diyl-alt-5,5′-di(thiophen-2-yl)-2,2′-(E)-2-(2-(thiophen-2-yl)vinyl)thiophene]} (PNVTs) based onnaphthalenediimide (NDI) acceptor and (E)-2-(2-(thiophen-2-yl)vinyl)thiophenedonor. The incorporations of vinyl linkages into polymer backbonesmaintain the energy levels of the lowest unoccupied molecular orbitsat −3.90 eV, therefore facilitating the electron injection.Moreover, the energy levels of the highest occupied molecular orbitsincrease from −5.82 to −5.61 eV, successfully decreasingthe hole injection barrier. Atomic force microscopy measurements indicatethat PNVTs thin films exhibit larger polycrystalline grains comparedwith that of poly{[N, N′-bis(2-octyldodecyl)-1,4,5,8-naphthalenediimide-2,6-diyl]-alt- 5,5′-(2,2′-bithiophene)}[P(NDI2OD-T2)], consistent with the stronger π–πstacking measured by grazing incidenceX-ray scatting. To optimize devices performance, field-effect transistors(FETs) with three devices configurations have been investigated. Theresults indicate that the electron mobility of the vinyl-containingPNVTs exhibit about 3–5 times higher than that of P(NDI2OD-T2).Additionally, the vinyl-linkages in PNVTs remarkably enhance ambipolartransport of their top-gate FETs, obtaining high hole and electronmobilities of 0.30 and 1.57 cm2V–1s–1, respectively, which are among the highest valuesreported to date for the NDI-based polymers. Most importantly, ambipolarinverters have been realized in ambient, exhibiting a high gain of155. These results provide important progresses in solution-processedambipolar polymeric FETs and complementary-like inverters. [ABSTRACT FROM AUTHOR]

Two tetrabrominated intermediates obtained by bromination of naphthodithiophene in different solvents were used to construct novel highly π-extended butterfly-shaped heteroarenes 1–6, containing either an 8- or 10-fused ring. The solution-processed organic field-effect transistors based on compound 1exhibited promising device performance with a hole mobility of 0.072 cm2V–1s–1and a current on/off ratio of 106under ambient atmosphere. [ABSTRACT FROM AUTHOR]