Main-chain conjugated polymers

Initial results for the main-chain conjugated polymers have already been demonstrated that the full spectrum of colors (red, green, and blue) can be realized with impressive efficiency, brightness, and uniformity. Main-chain conjugated polymers... 

Another effort to prepare a soluble main-chain conjugated polymer was made by Holmes, Bradley and co-workers (67-69J. The nitrile-substituted PPV derivative (cyano-PPV) was synthesized by the Wittig reaction and was soluble in common organic solvents. This polymer has high electron afflnity because of the electron-attracting nitrile group. 

The observed red shift of the absorption bands means that electronic interaction between neighboring fluorene units in the ground state lowered the excitation energy of the oligomers or polymers. In main-chain conjugated polymers, a longer chain... 

Among various main-chain conjugated polymers, one of the most practically used may be the poly(3,4-ethylenedioxythiophene) (PEDOT)-poly(styrenesulfonate) (PSS) mixture [121-124], PEDOT is a polythiophene derivative that can be doped using sulfonic acid including PSS and redox active metals. Since the fraction of PSS is higher than that of PEDOT in commercial aqueous solutions, the material is acidic. Also due to long main-chain conjugation PEDOT-PSS shows deep blue color. These two characteristics somewhat limit applications of PEDOT-PSS. 

Organic polymers for magnetism are classified into three categories (1) polymers with organic radicals in the side chains, (2) main-chain conjugated polymers with organic radicals, and (3) two-dimensional polyradicals. 

Besides these monodentate ligands, many multidentate ones have been prepared and used in different fields of chemistry and only a few should be mentioned here. Rigid bidentate benzimidazole-based N-heterocyclic carbenes were successfully used to synthesize main-chain conjugated organometallic polymers 23, an interesting class of materials with desirable electronic and mechanical properties (Fig. 9) [110]. 

Polyferrocenylene exhibits significant electrical conductivity when doped (see Section 12.06.3.2.1) and, thus, the introduction of ferrocene units into the main chain of polymers with cr-, ct-tt-, or 7r-conjugation in the backbone is a potentially appealing research objective. Studies of materials with short spacers were provided in Section 12.06.3 here we focus on polymers with spacers longer than three atoms. 

Izumi A, Teraguchi M, Nomura R, Masuda T. 2000a. Synthesis of conjugated polymers with azobenzene moieties in the main chain. J Polym Sci, Part A 38(7) 1057 1063. 

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