Functionalization of conjugated polymers

Y. Li, G. Vamvounis, J. Yu, and S. Holdcroft, A novel and versatile methodology for functionalization of conjugated polymers. Transformation of poly(3-bromo-4-hexylthiophene) via palladium-catalyzed coupling chemistry, Macromolecules, 34 3130-3132, 2001. 

The last few years have now brought about a qualitative new development, as a consequence of considerable advances in the available synthetic methods. In the 70s and 80s purely synthetic aspects were in the forefront, whereas during the following years the effective physical function of conjugated polymers has progressively become... 

Optical and Photonic Functions of Conjugated Polymer Superlattices and Porphyrin Arrays Connected with Molecular Wires... 

In the remainder of this chapter, we will discuss how the unique properties and functions of conjugated polymers can be incorporated into various types of microsystems, starting with sensors. The limitations of current MEMS materials are discussed in the context of specific examples. A more speculative discussion of the possible use of conjugated polymers in entirely new microsystems is considered at the end of the chapter. 

Shimidzu, T., T. lyoda, and H. Segawa (1996). Advanced materials by functionalization of conjugated polymers. Macromol. Symp. 101, 207-218. 

Y. Li, K. Kamata, S. Asaoka, T. Yamagishi and T. lyoda. Efficient anodic pyridination of poly(3-hexylthiophene) toward post-functionalization of conjugated polymers. Org. Biomol. Chem. (1), 1779-1784 (2003). 

Shimidzu T, lyoda T, Segawa H (1996) Advanced matraials by functionalization of conjugated polymers. Macromol Symp 101 127—135... 

There have been numerous studies of the electrical and emission properties of conjugated polymer-, small molecule-, and molecularly doped polymer-based OLEDs. The current-voltage and radiance-voltage characteristics have been nica sured as a function of thickness of the organic layer, temperature, different metal electrodes, etc. in an attempt to understand the device physics. A major factor in hibiting progress is the purity of the organic impurities that are incorporated dur-... 

Section 1.2 gives a brief review of conjugated polymers in semiconducting and metallic phases. Section 1.3 discusses device architectures and their corresponding processes. Section 1.4 introduces some novel devices and their functions in thin-film polymer devices. Section 1.5 is devoted to technical merits of SMOLEDs and PLEDs used as emitter elements in flat-panel displays. 

Although the exact mechanism of the fluorenone formation is not known, it is believed that the monoalkylated fluorene moieties, present as impurities in poly(dialkylfluorenes), are the sites most sensitive to oxidation. The deprotonation of rather acidic C(9)—H protons by residue on Ni(0) catalyst, routinely used in polymerization or by metal (e.g., calcium) cathode in LED devices form a very reactive anion, which can easily react with oxygen to form peroxides (Scheme 2.26) [293], The latter are unstable species and can decompose to give the fluorenone moiety. It should also be noted that the interaction of low work-function metals with films of conjugated polymers in PLED is a more complex phenomenon and the mechanisms of the quenching of PF luminescence by a calcium cathode was studied by Stoessel et al. [300],... 

However, the particular synthetic requirements in the preparation of conjugated polymers have thus far severely limited the number of similarly hierarchically structured examples. Pu et al. reported different types of conjugated polymers with fixed main-chain chirality containing binaphthyl units in their backbone which exhibited, for example, nonlinear optical activity or were used as enantioselective fluorescent sensors [42—46]. Some chirally substituted poly(thiophene)s were observed to form helical superstructures in solution [47-51], Okamoto and coworkers reported excess helicity in nonchiral, functional poly(phenyl acetylenejs upon supramolecular interactions with chiral additives, and they were able to induce a switch between unordered forms as well as helical forms with opposite helical senses [37, 52, 53]. 

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