A 7,7,8,8-tetracyanoquinodimethane polyester was converted into a strongly colored polyester with low-energy charge-transfer (CT) bands by treatment with electron-rich alkyne molecules under mild conditions. The post-functionalization was monitored by its ultraviolet-visible-near infrared (IR) spectra, which suggested a quantitative addition reaction without any side reactions. This result was further supported by 1 H and 13 C nuclear magnetic resonance, IR and elemental analyses. The functionalized polymer retained a high thermal stability with a decomposition onset temperature of B200 1C and B63% residual soot at 500 1C. The CT chromophores in the polymer showed a clear positive solvatochromism and redox behaviors in both anodic and cathodic directions. The HOMO and LUMO levels estimated from the first oxidation potential (E ox,1 ) and the first reduction potential (E red,1 ), respectively, were markedly elevated by this post-functionalization. The extent of HOMO elevation (1.45 eV) was more significant than that of LUMO elevation (0.44 eV).

Covalent incorporations into polymers of fullerene were achieved via the Cu(I)-catalyzed azide−alkyne click polymerizations of a fullerene derivative monomer functionalized with 5-(trimethylsilyl)pent-4-yn-1-yl groups and a comonomer functionalized with azidomethyl groups, producing the novel fullerene polymers P1-C 60 and P2-C 60 . Despite their extremely high fullerene loading levels, the polymers were soluble in common organic solvents and exhibited no aggregation of fullerene units in films. Moreover, devices containing these fullerene polymers were easily fabricated with common coating processes that exhibit excellent unipolar and bipolar flash memory characteristics as well as unipolar permanent memory characteristics, with high ON/OFF current ratios, long retention times, and low power consumption. These electrical switching behaviors were favorably operated by electron injection. Overall, these devices are the first n-type bipolar and unipolar digital polymer memory devices which can be operated in flash and write-once-read-many-times modes.

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Electron-rich, side chain alkynes of an aromatic polyamine were functionalized by a [2?2] cycloaddition, followed by retro-cyclization with the electronaccepting 7,7,8,8-tetracyanoquinodimethane (TCNQ). 1 H NMR studies were used to optimize the reaction conditions. Mild heating to [50°C afforded the postfunctionalized aromatic polyamines with the desired acceptor amounts. The quantitative TCNQ addition was demonstrated by the MALDI-TOF mass spectrum and elemental analysis. Introduction of the cyano-based acceptor moieties into the polymer side chains resulted in unusually strong intermolecular interactions. In addition to the p-p interactions of the extended acceptor moieties, these intermolecular forces were supposed to improve the thermal stability of the aromatic polymers. Furthermore, the donor-acceptor chromophores formed by this postfunctionalization displayed low energy charge-transfer bands and redox activities in both the anodic and cathodic directions. The straightforward postfunctionalization technique using the alkyne-TCNQ addition is useful for the preparation of narrow band gap polymers in one step.

Blue, green, and red light emitting conjugated copolymers based on the 1,8-linked carbazole unit were synthesized by the Sonogashira polycondensation between the 1,8-diethynylcarbazole derivative and arylene dibromide comonomers. The mixture of three polycarbazoles at a suitable molar ratio provided the white light emission in solutions.