Poly heteroarylenes

Recently, a poly(heteroarylene sulfide) formed by the reaction between bis(thiophenols) and bis(6-chlorophe-nyl quinoxalines) has been reported by Hedrick et al. [58]. 

Bunz et al. pointed out that it would be of interest to develop materials that combine the stability, electron affinity, and high emissive quantum yield of PPEs with the excellent hole injection capabilities of poly(p-phenylene vinylene)s (PPVs) [48]. In line with this notion,recent synthetic activities have focused on the engineering of the band gap, conduction band, and valence band of PAEs with the objective to render these materials more useful for practical applications that exploit their electrically (semi)conducting nature. Examples of materials that emerged from these efforts are discussed in detail in other portions of this volume (in particular the chapters by Bunz, Klemm, and Yamamoto). They include, among others, poly(heteroarylene ethynylenes) such... 

A method for modifying a poly(arylene-vinylene) or poly(heteroarylene vinylene) precursor polymer with dithiocarbamate moieties has been described [151,152]. 

Poly(heteroarylene methines) Characterisation, effect of structure on optical properties [61]... 

Jenekhe has also developed a extensive series of poly-(heteroarylene-methylene)s, LXXXIII [149,150]. These systems also have small band gaps (<1.5 eV) and iodine-doped conductivities of 10 -10 S/cm (undoped <10- S/cm) [150]. 

In two 1995 papers Chen and Jenekhe [130,131] describe the synthesis of poly(heteroarylene-methylenes), which are precursor polymers, and then the syntheses of a series of low band gap poly(heteroarylene methines) from these. Band gaps as low as 1.14 eV were observed for these polymers [4,129]. The first paper gives the synthesis of 20 new methylene-bridged polythiophenes of... 

The advantage of the activated displacement polymerization is the facile incorporation of different and unconventional structural units in the polymer backbone. Most of the heteroarylene activated polyethers prepared by this route are soluble in many organic solvents. The solubility behavior of new polyethers is shown in Table 8. In contrast to many polyphenylenequi-noxalines, poly(aryl ether phenylquinoxalines) prepared by the quionoxaline activated displacement reaction are soluble in NMP. Solubility in NMP is important since it is frequently used for polymer processing in the microelectronics industry [27]. 

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