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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]

A series of new n-type copolymers based on perylene diimide(PDI) or naphthalene diimide (NDI) and phenothiazine (PTZ) with differentside chain length and molecular weight have been designed and synthesizedby Pd-catalyzed Suzuki coupling polymerization with or without phase-transfercatalyst Aliquat 336. The effects of main chain, side chain, and molecularweight on the thermal, optical, electronic, and charge transport propertiesof the polymers have been investigated. Aliquat 336 improves molecularweight as well as reduces polydispersity index of the polymers. Allthe polymers exhibit a broad absorption extending from 300 to 900nm. The main chain and side chain structure and molecular weight haveminor effects on the HOMO (−5.8 to −5.9 eV) and LUMO(−3.7 to −3.8 eV) levels of the polymers. n-Channelfield-effect transistors with bottom-gate top-contact geometry basedon these copolymers exhibit electron mobilities as high as 0.05 cm2V–1s–1and on/off ratiosas high as 105in nitrogen, which are among the best reportedfor rylene diimide-based polymers under the same test conditions. [ABSTRACT FROM AUTHOR]