Cyclopentadithiophene polymers

The effect of bridging atoms and side chains on the structure and crystallinity of cyclopentadithiophene—henzothiadiazole polymers was studied (14CM1226). These workers demonstrated that hy combining quantum chemistry, molecular modeling, and scattering data, the effect of subtle chemical changes such as heteroatom substitution on polymer structure and properties, could be demonstrated. 

Bakhshi, A.K., Deepika, and J. Ladrk. 1997. Ah initio study of the electronic structures of polycyclopentadithiophene-4-one and polydicyanomethylene-cyclopentadithiophene Two conjugated polymers with small band gaps. Solid State Commun 101 347. 

Jenekhe, Watson, and coworkers [277] reported synthesizing three new donor-acceptor conjugated polymers incorporating thieno[3,4-c]pyrrole-4,6-dione acceptor and dialkoxybithiophene or cyclopentadithiophene donor units. The thieno[3,4-c]pyrrole-4,6-dione acceptor containing materials were studied in bulk heterojunction solar cells and organic field-effect transistors. The polymers had... 

Water-soluble polycationic and polyanionic cyclopentadithiophenes have been obtained by anodic electropolymerization of 34, where R = H and R = (CH2)6N(CH3)3+ and (012)4803 , respectively [105]. Although the polymers only attain a degree of polymerization of 5-6, the absorption maxima (560-575 nm) probably approach that of the maximum effective conjugation length [85]. Both polymers were obtained as water-soluble materials, depending on the nature of the counterion, and could be electrostatically self-assembled into ordered films. 

In parallel, Mullen and co-workers [106] and Zhu et al. [107] reported new copolymers based on an alternating cyclopentadithiophene-benzothiadiazole structure (entries 33 and 34, Table 3.1). These donor-acceptor polymers have shown excellent OFET and OPV device characteristics. The octadecyl... 

A decrease of the E° value in polythiophene-type polymers can be obtained only if the spacer is an electron-rich system. The electron-releasing effect of the alkyl group in the cyclopentadithiophene 21 (CPDT), coupled with the advantage, relative to alkyl-substituted thiophenes as monomers, of treating a planar system, and the jr-excessive nature of the pyrrole ring in 22 have been exploited [223,224]. In fact, the E° values of the polymers derived from both 21 and 22 are definitely lower than that of polythiophene, with the consequence that they should be much more reluctant to react with reducing agents and nucleophiles. 

Lee SK, Cho NS, Cho S, Moon S-J, Lee JK, Bazan GC (2009) Synthesis and chaiacterizatimi of low-bandgap cyclopentadithiophene-biselenophene copolymta- and its use in field-effect transistor and polymer solar cells. J Polym Sci A Polym Chem 47 6873... 

A series of 4-alkyl- 225 and 4,4 -dialkyl-substituted cyclopentadithiophenes 226 synthesized and polymerized by Berlin and Zotti et al. resulted in soluble and highly conductive polymers. The partial rigidity of the polythiophene backbone causes anomalously red-shifted absorption spectra in the neutral state which... 

Horie M, Majewski LA, Feam MJ, Yu C-Y, Luo Y, Song A, Saunders BR, Turner ML (2010) Cyclopentadithiophene based polymers-a comparison of optical, electrochemical and organic field-effect transistor characteristics. J Mater Chem 20 4347-4355... 

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