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Broadband dielectric measurements of poly(vinyl pyrrolidone) (PVP)-monohydroxyl alcohol mixtures of various normal alcohols are made in the frequency range of 20 Hz to 20 GHz at 25 degree Celsius. The results have shown that the relaxation time of the local chain motion of PVP increases with PVP concentration and solvent viscosity.

Fabry-Perot fringes are observed in the absorption spectra of hydrogen-bonded layer-by-layer (LBL) films of poly(vinyl pyrrolidone) (PVPON) and ploy(acrylic acid) (PAA), which are obtained from the interferences between beams transmitted and partially reflected at the highly smooth film-air interface and film-quartz interface. The PVPON/PAA films are eroded by long-term annealing in water or diluted HCl by monitoring the movement of the Fabry-Perot fringes and the erosion rate is found to decrease with a decrease in the pH of the media and an increase in the molecular weight of the polymers.

Spin trapping by 5,5-dimethylpyrroline-N-oxide (DMPO) is used for the detection of radicals in Fenton media in the presence and absence of Nafion perfluorinated ionomers. The formation and trapping of solvent-derived free radicals in ethanol and in methanol is one of the major limitations of DMPO as a spin trap for radical identification in Fenton media, but for water as solvent, the method can be useful when the polymer is treated at higher than ambient temperatures.

The polypyrrole/palladium composite film is prepared on the glassy carbon electrode by electrodepositing method. The X-ray photoelectron spectroscopy has shown a strong interaction between polypyrrole film and palladium particles and this modified electrode has shown an excellent current efficiency for electrochemical hydrogenation of 4-chlorophenol, where phenol is the sole product.

Various surfactants and oxidizing agents are used together for the controllable synthesis of wire-, ribbon-, and sphere-like nanostructures of polypyrrole by polymerization. The analysis shows that the morphologies of the resulting polypyrrole nanostructures are greatly dependant on the monomer concentration, surfactant concentration, and surface chain length, which gives pure and doped nanostructures.

Two-dimensional gold nanostructures was fabricated by electrochemical deposition of gold nanoparticles onto indium tin oxide (ITO) glass substrate modified with thin polypyrrole film. By controlling the electrodeposition conditions, gold nanoparticles with dendritic rod, sheet, flower-like, and pinecone-like structures were generated and the flower-like gold nanoparticles showed high catalytic activity on electrochemical reduction of oxygen.

N,N-Dimethyl-pyrrolidinium iodine, and effect of doping with LiI, was investigated using differential scanning calorimeter (DSC), NMR, and impedance spectroscopy. A slight decrease in phase transition onset temperatures, as well as the appearance of a superimposed narrow line in the (super 1)H NMR spectra with dopant, suggests that the LiI facilitates the mobility of the matrix material, possibly by the introduction of vacancies within the lattice.

The electrochemical stability of 10 organic cations, which can be used in ionic liquids, was investigated as solutes in acetonitrile. The stability of three of the salts, BenMe2EtNcl (salt III), 1-butyl-2-methyl pyrrolidium chloride salt (salt VI), and its structural isomer, BuMe2ProNCl (salt VII) were compared in chloroaluminate ionic liquids (ILs).

Laccase catalyzes the polymerization of pyrrole into a conducting polymer using dioxygen as the terminal oxidant. The charge transport properties of the resulting polymers, both with and without 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) as the counteranion, are compared to those of other conducting materials including polypyrrole prepared electrochemically or chemically.

The effects of the polymerization temperature and of voltammetric cycling on the chain length and the resistivity of polypyrrole films are investigated. As the electropolymerization of conjugated systems in contrast to normal polymerization reactions is a fully activated process, the generation of the different types of polypyrrole depends on experimental parameters such as temperature or formation potentials.

The polypyrrole/poly(vinyl sulfonate) (PPy/PVS) films in acetonitrile containing 0.1 M LiC1O(sub 4) were studied by cyclic voltammetry. The result was confirmed by 'ex situ' energy-dispersive X-ray analysis of the films and the increase and shift of the voltammetric cycles indicated a restructuring of the polymeric chains with consecutive scans.

The electroactivity of electrogenerated polypyrrole films is degraded by applying consecutive anodic potential pulses. The charge consumed during each degradation step is calculated by the difference between the degradation ad the control chronoamperograms.

A strategy to electrodeposit polypyrrole (PPy) or roughened silver substrates, accomplished by a triangular-wave oxidation-reduction cycle (ORC) for three scans in an aqueous solution containing 0.1 N KCl is studied. Different view on how Raman spectroscopy has proved to be an effective means to evaluate the structure situation of PPy in various states.

A model with atomic detail of the polypyrrole/water system is simulated in both the oxidized (charged) and reduced (uncharged) polymer. From the simulated trajectories, macroscopic properties, such as the polypyrrole density in its reduced state and polymer swelling after oxidation, are simulated.

The potentiostatic synthesis and microgravimetric kinetics of hybrid materials polypyrrole/PW12O40(super 3-) are investigated. The results show that the mechanism of the electropolymerization process does not change in significant way when the conditions of synthesis are changed.

The first electrochemical oxidation-reduction cycle procedure to roughen gold substrates in 0.1 N HCl aqueous solutions containing 1 nM rutile TiO2 nanoparticles under the irradaition of UV light is presented. The SERS spectrum of polypyrrole electrodeposited on the corresponding roughened gold substrate exhibits a 5-fold higher intensity compared to that without he contribution of TiO2 nanoparticles.

Ab initio quantum mechanical calculations were used to study the stability of hydrogen-bonded complexes formed by pyrrole and thiophene, which are the most common building blocks of conducting polymers, and DNA bases. The results shed light on the ability of polypyrrole to interact and stabilize adducts with DNA and the weaker and nonspecific interaction of polythiophene and their derivatives.

The conductivity relaxation measurements in wide range of temperature and pressures were used to study the ion dynamics under pressure in the ionic liquid 1-butyl-1-methylpyrrolidinium bis[oxalate]-borate (BMP-BOB). The results showed that the dynamic response under pressure in the ionic liquid is identical to that found in nonionic glass formers.

An situ chemical oxidative polymerization with HCl as the dopant and ammonium persulfate (APS) as the oxidant was used to prepare electromagnetic functionalized polypyrrole/Ba[Fe.sub.12][O.sub.19] (PPY/BF) microstructural composites. The results revealed that a slight overdose of the pyrrole monomer leads to PPY composites with an accurate control of the core/shell mass ratio.

A detailed thermodynamic study on a calix[4]pyrrole derivative, meso-tetramethyl-tetrakis-(4-hydroxyphenyl)calix[4]pyrrole that resembles the calix[4]arene was conducted to assess its capacity to remove the phosphate anion from aqueous solutions. The results indicate that calix-pyrrole resin is suitable for the removal and recovery of [H.sub.2]P[O.sub.4.sup.-] ions from aqueous media, which is influenced by parameters such as initial anion and resin concentration, pH, and temperature.

A detailed analysis of the mechanism of photoinduced electron and proton transfer in the planar pyrrole-pyridine hydrogen-bonded system, a potential model of the characteristic ultrafast hydrogen bond photochemistry of DNA base pairs is presented.

Intrinsically self-stabilized nanoparticles of a copolymer from 4-sulfonic diphenylamine (SD) and pyrrole (PY) are facilely synthesized in HCl solution by a chemically oxidative polymerization. The copolymer nanoparticles have displayed high purity, clean surfaces, good self-stability, high conductivity and strong chemoresistance that are vital for nanomaterial processibility and application.

The synthesis and characterization of two sulfur-containing hybrid calix[4]pyrrole derivatives are presented. The results have shown that replacement of one or more pyrrole units by thiophene rings in calix[4]pyrrole has tuned the discrimination ability of the ligands between anions and has enabled the produced hybrid calixpyrroles to bind selectively with Hg(II) in acetonitrile.

Intrinsically self-stabilized nanoparticles of a copolymer from 4-sulfonic diphenylamine (SD) and pyrrole (PY) are facilely synthesized in HCl solution by a chemically oxidative polymerization. The copolymer nanoparticles have displayed high purity, clean surfaces, good self-stability, high conductivity and strong chemoresistance that are vital for nanomaterial processibility and application.

The synthesis and characterization of two sulfur-containing hybrid calix[4]pyrrole derivatives are presented. The results have shown that replacement of one or more pyrrole units by thiophene rings in calix[4]pyrrole has tuned the discrimination ability of the ligands between anions and has enabled the produced hybrid calixpyrroles to bind selectively with Hg(II) in acetonitrile.

Two artificial photosynthetic antenna models consisting of a Si phthalocyanine (Pc) bearing two axially attached carotenoid moieties having either 9 or 10 conjugated double bonds are used to illustrate the functions of carotenoids in photosynthetic membranes. The results have suggested the association of either inner- or intramolecular charge-transfer species involving carotenoids during the process of excess energy dissipation in photosystem II.