Polythiophene poly

Fig. 17 (a) Chemical structure of polythiophene poly((3,3"-di[(S)-5-amino-5-carbonyl-3-oxapen-tyl]-[2,2 5 2"])-5-,5"-terthiophenylene hydrochloride), PONT, (b) Emission spectra of 6.5 pM PONT—HC1 (on a chain basis) in 25 mM HC1 (black spectrum), 25 mM HC1 with 5.0 pM of native bovine insulin (blue spectrum), 25 mM HC1 with 5.0 pM fibrillar bovine insulin (red spectrum). The emission spectra were recorded with excitation at 400 nm [31]... 

An extensive review of the synthesis of rc-conjugated polymers is presented using a tutorial approach to provide an introduction to the field intended for the undergraduate student and the experienced chemist alike. The many synthetic methodologies that have been used for the synthesis of conjugated polymers are outlined for each class of polymers with a focus on research from the 1990s. The effect of structure on electrical properties is detailed. Specific systems reviewed include the polyacetylenes, polyanilines, polypyrroles, polythiophenes, poly(arylene vinylenes), and polyphenylenes. 

Keywords Conducting polymers, Conjugated polymers, Polyacetylenes, Polyanilines, Polypyrroles, Polythiophenes, Poly(arylene vinylenes), Polyphenylenes... 

Polymers (CH), PPA Poiy(o-Me3SiPA) PPY DP-PPY PPY PAN PNA EM LM NA PTH PPS PBT PBiT PMeT PHeT PPV PPP P2VP P4VP PVK polyacetylene polyphenylacetylene poly[[o-(trimethylsilyl)phenyl]acetylene] polypyrrole deprotonated (25%) polypyrrole fully reduced polypyrrole polyaniline pernigraniline emeraldine leucoemeraldine nigraniline polythiophene poly(phenylene sulfide) polybenzothiophene poly(2,2 -bithiophene) poly(3-methylthiophene) poly(3-hexylthiophene) poly(phenylene vinylene) poly( p-phenylene) poly(2-vinylpyridine) poly(4-vinylpyridine) poly(A-vinylcarbazole)... 

Composites of polypyrrole and poly(vinyl chloride) have been prepared by several groups (64-67). Polythiophene-poly(vinyl chloride) composites have also been prepared (68). The electropolymerization of pyrrole on poly(vinyl chloride)-coated electrodes yielded composites with mechanical properties (tensile strength, percent elongation at break, percent elongation at yield) similar to poly(vinyl chloride) (65) but with a conductivity of 5-50 S/cm, which is only slightly inferior to polypyrrole (30-60 S/cm) prepared under similar conditions. In addition, the environmental stability was enhanced. Morphological studies (69) showed that the polypyrrole was not uniformly distributed in the film and had polypyrrole-rich layers next to the electrode. Similarly, poly(vinyl alcohol) (70) poly[(vinylidine chloride)-co-(trifluoroethylene)] (69) and brominated poly(vinyl carbazole) (71) have been used as the matrix polymers. The chemical polymerization of pyrrole in a poly(vinyl alcohol) matrix by ferric chloride and potassium ferricyanide also yielded conducting composites with conductivities of 10 S/cm (72-74). 

The chiral polythiophene, poly(3- (.S )-5-amino-5-carboxyl-3-oxapcntyl -2,5-thiophenylene) hydrochloride, l-POWT, ring-functionalized with the amino acid L-serine, has been synthesized by Inganas and coworkers,69,168 and was found to exhibit pH-dependent UV-visible, fluorescence emission, and CD spectra. At a pH equal to the isoelectric point of the amino acid, the poly thiophene chains separate and adopt a nonplanar right-handed helical conformation. Increasing the pH leads to a more planar conformation of the backbone and aggregation of the polymer chains. 

Conductive conjugated polymers belonging to polyenes or polyaromatics, such as polyacetylene, polyanUine (PANl), polypyrrole (PPy), polythiophene, poly(p-phenylene), and poly(phenylene vinylene) classes, have been investigated extensively [1-3]. PANI and PPy families of conjugated polymers are of much interest due to their low cost, easy synthesis, unique conduction mechanism, good stability and environmentally benign performance [4,5],... 

Department of Materials Science and Engineering, University of Cincinnati, Ohio Polypyrrole Polyquinoline Polythiophene Poly (p-xylylene)... 

The thiophene family of conducting polymers offers unique flexibility for tailoring of polymer properties as a result of the ease of functionalization of the parent monomer, i.e., an ester-functionalized organic solvent-soluble polythiophene [poly-octanoic acid 2-thiophen-3-yi-ethyi ester) changing the properties of PTh and resulting from post-polymerization hydrolysis of the ester linkage. The polymer films supported the proliferation and differentiation of both primary and... 

One of the early known conductive polymers is polysulfumitride (SN) ,, an inorganic material that tends to be explosive, but becomes superconducting at 0.3 K [63]. Since then many other conductive polymers evolved. The most investigated ones appear to be polyacetylene, polyaniline, polypyrrole, polythiophene, poly(phenylene sulfide), and poly(phenylene vinylene) and their derivatives. Many derivatives of these materials and other similar ones also been reported. 

Synthesis of a water-soluble, phosphonic acid derivatized, polythiophene, poly(3-(3 -thienyloxy)propanephosphonate) has been reported by Viinikanoja et al. [55]. The polymerizations of both 3-(3 -thienyloxy) propanephosphonic acid and its sodium salt were unsuccessful however an ethyl ester form was electropolymerized in 0.1 M lithium perchlorate/acetonitrilerdichloromethane (1 1) at 1.8 V vs sodium SCE. 

First, it is worth noting that some polythiophene derivatives do not display good n-doping behavior. This is the case for unsubstituted polythiophene, poly(3-methylthiophene) and poly(3,4-ethylenedioxythiophene) (PEDOT). Nonetheless, it will be shown below that they could be useful as positive electrode materials in hybrid electrochemical capacitors. 

The conductivities of the poly[C CPDT]s are particularly high (25-300 S cm" ), in line with most conductive polythiophenes. Poly[(C )2CPDT]s are on the... 

Whereas the cyclic voltammograms of poly(CPDT) and poly(C CPDT) display the twin oxidative response usually found in polythiophenes, poly[(C )2CPDT] films are characterized by a single well-defined redox response. 

The novel functionalized polythiophenes, poly[3-(6-hydroxyhexyl)thiophene] and poly(3-octanethio-2,2 -bithiophene), have been used as selective coating materials for quartz crystal microbalance (QCM) sensors. These Langmuir-Blodgett film coated QCM sensors are useful in detecting heavy metal ions in aqueous solution, which are major pollutants in wastewater (54). 

With the objective of preparing fiber optic chemical sensors for pH measiu ements, Millar et al. have recently synthesized a polythiophene poly(27) derivatized by a pH-sensitive fluorescein unit [343]. As expected, the fluorescence properties of the polymer... 

Roncali et al. [1030] studied a series of 3-substituted polythiophenes [poly(3-methylthiophene) (PMT), poly(3-isoamylthiophe-ne) (PiAT), poly(3-nonylthiophene) (PN, and poly(3-3,6-dioxy-heptylthiophene) (PDHT)]. The symmetry of the current waves increases in the given ranking, implying an enhanced reversibility of... 

Mode Polythiophene Poly(3-decylthiophene) Poly(3,3 -dibutoxy-2,2 -bithiophene) ... 

By certain physical factors like thermal, ultraviolet irradiation, high pressure and other chemical parameters like organic solvents the helical pol5mers are easily denaturalized. A variety of helical polymers are synthesized, which include polyisocyanates, polyisocyanides, polychloral, polymethacrylates, polysilanes, polythiophenes, poly (p-phenylene)s, poly(l-methylpropargyl-ester)s, poly(phenylacetylene)s and poly (-unsaturated ketone) [18-24] (Fig. 1). Other polymers are whose optical activity is main chain or side chain chirality dependent e.g. amino-acid-based polymers are nontoxic, biocompatible and biodegradable. 

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