Chemical polyfluorenes

J. Cornil, I. Gueli, A. Dkhissi, J.C. Sancho-Garcia, E. Hennebicq, J.P. Calbert, V. Lemaur, D. Beljonne, and J.L. Bredas, Electronic and optical properties of polyfluorene and fluorene-based copolymers a quantum-chemical characterization, J. Chem. Phys., 118 6615-6623, 2003. 

I. Franco and S. Tretiak, Electron-vibrational relaxation of photoexcited polyfluorenes in the presence of chemical defects a theoretical study, Chem. Phys. Lett., 372 403-408, 2003. 

CHART 4.26 Chemical structure of green-emitting and red-emitting phosphorescent polyfluorenes. 

From the late 1970s onwards, efforts to synthesise conjugated polymers rapidly expanded and numerous new materials were prepared. Many of these still proved to be intractable substances that were difficult if not impossible to purify and characterise. The maximum levels of conductivity achieved on doping often fell well short of the metallic range. Such properties meant that the majority of these materials attracted little attention beyond the initial reports, and certainly no commercial interest. An example of the few polymers produced at this time that have been extensively studied subsequently is polythiophene (PTh), Fig. 9.2(h). Although this polymer was also reported in the nineteenth century (Meyer, 1883), the first reliable synthesis appeared in 1980, see McCullough (1998). Another example is polyfluorene, Fig. 9.2(i), which was prepared chemically and electrochemically in 1985, see Rault-Berthelot and Simonet (1986). Much subsequent synthesis has been directed to the inclusion of pendent groups to either enhance solubility,... 

Most research effort, therefore, concentrated on those polymers where it is possible to control morphology, to obtain chemically pure materials and to manipulate them to provide forms, e.g. chain oriented samples and thin films, suitable for basic research and applications. The development of synthetic routes that provide clean, reproducible samples has been critical in the progress achieved in understanding the physics of conjugated polymers. This in turn underpinned the rapid development of technological applications, which appeared on a much shorter timescale than for other, comparable technologies. The level of scientific and technical interest in polymers, such as PAc, PAni, PPy, PThs, PPVs and polyfluorenes, has resulted in the commercial production of them and their precursors. 

Polyfluorenes (PFs), the simplest regular stepladder-type polyphenylenes, in which only every second ring is bridged, have been much studied in recent years due to their large PL quantum efficiencies and excellent chemical and... 

Introducing Ir(III) complexes into the side-chain using a chemical bond is an effective way to produce polyfluorenes with on-chain iridium cen-... 

Scheme 3 Chemical structures of polyfluorenes with on-chain Ir complexes...

Scheme 4 Chemical structure of white light-emitting polymer based on polyfluorene with Ir complex on the main-chain...

Scheme 7 Chemical structures of polyfluorenes with charged Ir(III) complexes in the main-chain...

Scheme 8 Chemical structure of polyfluorene derivatives with charged Ir(III) complex in the side-chain...

Scheme 10 Chemical structure of polyfluorene derivatives with on-chain Pt(II) complexes showing molecular wire behavior...

Scheme 15 Chemical structure of polyfluorenes with on-chain Ru(II) complex...

Fig. 4 Chemical structure of PDMOF and geometry of a polyfluorene derivative chain. Reprinted with permission from [28]. (2004) by the American Chemical Society...

Optically Active Chemical Defects in Polyfluorene-Type Polymers and Devices... 

Keywords Chemical defects Electroluminescence Light-emitting diodes Photoluminescence Polyfluorene-type polymers... 

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