Polymers from Thiophen

Kossmehl and G. Chatzitheodorou, Makromol. Chem., Rapid Commun., 1981, 2,551. 

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Polymers from Thiophens. - The mass spectra of polymers... 

Polymers from Thiophen Derivatives.—The bifunctionality of thiophen and its potential availability in large quantities at a low price has for many years attracted the interest of polymer chemists. However, progress has been slow. 2,5-Dichlorothiophen has been polymerized to a solid in 93% yield on treatment with aluminium chloride and cupric chloride in carbon disulphide. The product is believed to be poly-5-chloro-2,3-thienylene. Thiophen-2,5-dicarboxylic hydrazide was prepared by the reaction of thiophen-2,5-dicarbonyl chloride with the corresponding dihydrazide and then cyclodehydrated to poly-(thienylene-[2,5]-alt-l,3,4-oxadiazolylene-[2,5]-amer) (258) by polyphosphoric acid. This polymer could also be obtained directly from thiophen-2,5-dicarboxylic acid and hydrazine in oleum. The polymers produced were investigated in view of their thermal stability and as polymeric organic semiconductors. The same research... 

The synthesis of other poly(arylene ether)s containing thiophene units concerned the reaction of two activated halides containing thiophene (structures 8 and 9) with bisphenol A [44,45]. The polymers from the monomers of structures 8 and 9 and bisphenol A had intrinsic viscosities (NMP, 25 °C) of 1.23 and 0.43 dL/g and Tgs of 158 and 120°C, respectively. 

The electrosynthesis of polythiophene (PT) from thiophene must be performed under extremely anhydrous conditions, quite in contrast to polypyrrole [334]. Polymerization of 3-methylthiophene and bithiophene is much less sensitive to water. The advantage of PT is a higher theoretical capacity and a very positive potential (cf. Table 7). It is for these reasons that its application as a positive electrode in rechargeable lithium batteries [335-338] and in a metal-free PPy/PT cell [339] has been considered. Derivatives such as dithienothiophene [340] or rra/is-l,2-di(2-thienyl)ethylene [341] have also been polymerized, but the polymer materials suffer from low theoretical capacities [337]. 

Polymers containing heterocycles in the backbone include a variety of compounds, as the diversity of heterocyclic molecules is quite large. The polymers from this class may contain groups derived from furan, thiophene, pyrrole, isoindole, benzimidazole, benzothiazole, benzoxazole, quinoxaline, etc. Macromolecules with a ladder backbone containing, for example, a phenoxazine unit in their structure also are known. Amino thermosetting resins from melamine can be considered as polymers containing heterocycles in their structure. 

Depending on their structure, the polymers containing heterocycles have various applications. For example, poly(furfuryl alcohol) is used in composite materials with fillers such as sand and concrete, in copolymers with formaldehyde, etc. Some of the polymers from this group have special properties such as good electrical conductivity (after appropriate doping). Among these polymers are poly(thiophene-2,5-diyl) and particularly polypyrrole, CAS 109-97-7, (usually in carbon black doped with an organic acid anion). The structure of this polymer is shown below ... 

Bryce, M. R., Chissel, A., Kathirgamanthan, R, Parker, D., Smith, N. R. M., Soluble, Conducting Polymers from 3-Substituted Thiophenes and Pyrroles , J. Chem. Soc. Chem. Commun. (1987) 466-467. 

M. Armour, A. G. Davies, J. Upadhyay, and A. Wasserman, Colored electrically conducting polymers from furan, pyrrole and thiophene, J. Polym. Sci. A, 1, 1527-1538 (1967). 

Phenylthieno [3,4-fi] thiophene was synthesized using Brandsma s procedure [21] except that phe-nylacetylene was used to place the phenyl group on the 2-position of T34bT. Polymer from this monomer was obtained electrochemically, and was found to exhibit a band-edge gap of 0.82 eV and a Amax at 920-940 nm (Figure 11.8). 

Berlin, A., et al. 2004. New low-gap polymers from 3,4-ethylenedioxythiophene-bis-substituted electron-poor thiophenes. The roles of thiophene, donor-acceptor alternation, and copolymerization in intrinsic conductivity. Chem Mater 16 3667. 

Lee, B., M.S. Yavuz, and G.A. Sotzing. 2005. Gonjugated polymers from thieno [3,4-b] thiophene dimers. Polym Prepr (Am Chem Soc Div Polym Chem) 46 860. 

Sotzing, G.A., et al. 2003. Optically transparent conductive polymers from thieno[3,4-b]thiophene. Polym Mater Sci Eng 88 268. 

Recently, polymers prepared from thiophene-based conjugated systems 248 [441] or 249 [442] with covalently attached perylene bisimides have been reported. These polymers exhibit a broad absorption in the 400-800 nm range [442], which makes them potential candidates for PV apphcation. 

Belletete, M., L. Mazerolle, N. Desrosiers, M. Leclerc, and G. Durocher. 1995. Spectroscopy and photophysics of some oKgomers and polymers derived from thiophenes. Macromolecules 28 8587-8597. 

Bryce, M.R., et al. 1987. Soluble, conducting polymers from 3-substituted thiophenes and pyrroles. 7 Chem Soc Chem Commun (6) 466. 

Many thiophene derivatives have been polymerized in order to obtain new materials tailored for different purposes. Roncali [596] reviewed the enormous amount of literature regarding the synthesis, functionalization and applications of polythiophenes in 1992. Beside the polymerizations of thiophene and bithiophene, polymers from several thiophene oligomers, substituted thiophenes, thiophenes with... 

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