Solubility polypyrrole derivatives

In the same report, the authors describe the homopolymerization of 3-(pyrrol-1-yl)propanesulfo-nate via oxidative coupling with ferric chloride (Figure 20.33). A black insoluble precipitate in a dark solution was obtained. The latter was claimed to be the first water-soluble polypyrrole derivative. Pressed pellets of the insoluble traction and cast films of the soluble portion possessed electrical conductivities of 10 to 10 S cm . ... 

Polypyrrole derivatives [Fig. 13(a)] with nonionic substituents, producing films formed by oligomers these films are soluble in most organic solvents. 

A number of derivates of pyrroles have been polymerized and manipulated into multilayer structures using the Langmiur-Blodgett technique [203]. This technique has been applied to manipulate electroactive conjugated polymers, mainly polypyrrole derivates, into multilayer thin films with well-defined layered structures and ordered molecular organizations [204]. In this way, amphiphilic polypyrroles and their precursors have been used, or soluble surface-active polypyrroles such as poly(3,4-dibutylpyrrole) [205] (Schemes 10.11 and 10.12). 

In the synthesis of ferrocene-functionalized polypyrrole systems, numerous derivatives are readily obtained by substitution at either the 3-position of the ring or on the nitrogen of the pyrrole prior to polymerization. It was reported that polymers with both metallic properties and enhanced solubility may be synthesized by judicious derivatization and choice of polymerization conditions, such as a variety of processing solvents [67, 68]. 

An established technique for preparing soluble derivatives of intractable polymers is to add solubilizing substituents to the monomer. Thus, insoluble polyphenylenes have been rendered soluble (75) in common solvents such as chloroform by phenyl substitution. Similarly, a wide range of substituted pyrroles and thiophenes have been investigated to improve the tractability of these relatively stable conducting polymers. The chemical and electropolymerization of N-substituted pyrroles (76) gave polymers with substantially decreased conductivities, generally by a fector of 10 compared to polypyrrole. However, monomers substituted at the 3 and 4 positions of... 

Polyaniline is less tolerant of preparation conditions than polypyrrole, and the list of anion dopants used in the preparation is more limited. However, subsequent replacement of the anion used in preparation by a dodecylben-zene sulfonate makes polyaniline become soluble in solvents such as Af-methyl pyrrolidone (NMP), or zn-cresol, and it can be spin-coated or otherwise solution-processed. In a similar way derivatives of aniline, such as... 

Conjugated polymers, such as polypyrrole, pol3d hiophene, polyaniline (PANl) and its derivatives, are the most promising class of organic-semiconducting materials due to their better electrochemical behavior, electrochromism, ease of doping, and synthesis. But, on the other hand the low processability due to its low solubility is a problem. 

Since pyrrole and its derivatives form very stable conducting surfaces, Za-gal, Bedioui, and coworkers used ultramicro-carbon-fiber electrode modified with polypyrrole-dopped cobalt-tetrasulfonated phthalocyanine for the electrocatalytic oxidation of 2-ME The resulting electrode was stable and showed a detection limit of 8 10 M. Pyrolle substituted phthalocyanines have been used for the analysis of cysteine. Electrocatalytic behavior of MPc complexes has also been examined under homogeneous conditions. Water soluble OMo (OH)TSPc catalyzed the oxidation of cysteine under homogeneous conditions. ... 

The electropolymerization of o-methoxyaniline in the presence of (+)-(lS)- or (-)-(ll )-CSA yields an optically active polyaniline derivative. The polymer shows intense CD bands as a film deposited on an electrode. The polymer is soluble in NMP, CHCI3, DMF, DMSO, and MeOH, and the polymer also showed CD absorption in a solution probably based on a chiral main-chain conformation such as a helix. A film made by spin-coating a mixture of polyaniline with CSA also showed strong CD absorptions, which may be based on a helical conformation of the main chain. The electropolymerization method has been applied to the synthesis of an optically active polypyrrole which may have a helical conformation. ... 

The interaction of PC-12 cells, an immortal nervelike cell line derived from rat pheochromocytoma, with polypyrrole thin films doped with poly(styrene sulfonate) dopant has been studied by Shastri et al. [51,52]. Their studies have shown that PC-12 cells interact and differentiate in a more pronounced manner on polypyrrole substrates as compared with tissue culture polystyrene (TCPS) and poly(L-lactic acid) (PLA) controls in the presence of soluble NGF. Using quantitative image analysis techniques, it has been shown that both the number and length of neurites expressed by the cells on polypyrrole substrates are significantly greater... 

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