Thiophene-phenylene copolymers

Tuning the Properties of Substituted Phenylene-Thiophene Copolymers... 

Phenylene-thiophene copolymers 562b and 562a emit blue light at ca. 450-475 nm, with somewhat different reported ELex values of 0.2% (96AM982) and 0.03% (97MM4608) respectively, for ITO/polymer/Ca configurations. 

A series of four fluorene-phenylene vinylene copolymers 320-323 clearly demonstrates the effect of the exact position of CN groups in the vinylene fragment on the emission of the materials (Scheme 2.48) [408], Substitution of benzene rings in copolymers 320 and 321 by thiophene results in red-shifted PL and EL, where copolymers 322 and 323 exhibit pure red emission with chromaticity values very close to the standard red (CIE x = 0.66, y = 0.34), although no PLQY values were reported. The ITO/PEDOT/322/Ca/Al device showed a very... 

J.-H. Tsai, C.-C. Chueh, W.-C. Chen, C.-Y. Yu, G.-W. Hwang, C. Ting, E.-C. Chen, H.-F. Meng,NewThiophene-Phenylene-Thiophene Acceptor Random Conjugated Copolymers for Optoelectronic Applications. /. Polym. Sci. Part Polym. Chem. 2010,48,2351-2360. 

The polymerization processes described in this chapter may also impart a helical structure in heterocyclic conjugated polymers or aromatic systems that do not have chiral substituents in the side chain. In fact, in recent years various helical conjugated copolymers, such as poly thiophenes, polyethylenedioxythiophenes, and phenylene-thiophene, have been synthesized by electrochemical or chemical polymerization using the N -LC host phase [171-178]. 

Copolymer 459, prepared by Stille coupling of dibromophenylene with 2,5-Mv(tributyl-stannyl)thiophene, represents another example of a phenylene-u/t-thiophene backbone, where the substituted phenylene unit forms an oligophenylene vinylene fragment that is not in the main conjugation chain [561]. A PLED fabricated with this polymer (ITO/459/A1) emitted green light (520 nm) with a turn-on voltage of ca. 9.5 V, but no other data on luminance or efficiency of the device were reported (Chart 2.111). 

Fluorene-thiophene-phenylene copolymers 592-593 clearly demonstrate the effect of the exact position of CN groups in the vinylene fragment on the emission of the materials (04MM5265). 

Kinks in phenylene-based polyesters were also obtained by 2,5-thiophene dicarb-oxylate (ThA) moieties, which exhibit a core angle of 148° [12]. These copolymers exhibit stable nematic phases, but their transition temperatures are higher than those of the corresponding isophthalates. For example, the polyester composed of chlorohydro-quinone and 2,5-thiophene dicarboxylate [poly(ClHQ)/ThA] exhibits a melting transition around 410 °C with a clearing temperature above 500 °C (Fig. 7). In contrast, the corresponding polyester poly(ClHQ/TA) shows only a solid state transition at 375 °C and does not melt below 500 °C. The poly-... 

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