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Films of poly(propargyl alcohol) (POHP), doped with both sulphuric acid and iron trichloride, were deposited on interdigitated gold electrodes. Their electrical properties were examined as a function of percentage relative humidity. The devices showed low-frequency capacitance linearly dependent on RH% with good response time, and are proposed as possible capacitive humidity sensors

The electrical characteristics of oxidized poly(thionaphtheneindole) were investigated as a function of ambient relative humidity (r.h.). The current flowing through a pressed pellet of material between two massive gold electrodes plotted against voltage gives a wave-shaped curve with a halfwave potential at V <>=<>~3V. The current recorded at 4V (plateau of the wave) is a sigmoidal function of r.h. with the inflexion point at ~60%. An interpretation of these findings is given, based on the influence of water on the dielectric constant of the material and on acid–base equilibrium between poly(thionaphtheneindole) and water, from which protons are produced. The behaviour of poly (thionaphtheneindole) as the active component of an amperometric humidity sensor is also reported

The electrical properties of poly(propargyl alcohol), chemically doped with sulfuric acid, were investigated as a function of the relative humidity. In the absence of water, the conductivity of the doped polymer is very low (about 3 x 10-9 S cm-1 at 25 °C) with characteristics of electronic-type charge transfer. In the presence of humidity, the charge transfer inside the polymer is mainly due to proton motion and the conductivity, ionic in character, increases with exponential trend as a function of the relative humidity. An explanation of this behaviour is attempted by taking into account the effect of water on the ion interaction. A preliminary investigation on the possibility of the use of the acid-doped poly(propargyl alcohol) as humidity sensor was also carried out.

Two new compounds with four tertiary arylamine moieties connected in a fully para-conjugated system have been synthesised in order to obtain new molecules having low ionisation potentials, as required for hole transporting materials in organic light emitting diodes (OLEDs). Their electrochemical properties have been measured and compared to seven different commercial triarylamines tested in the same experimental conditions. Using the AM I geometries and the statistical average of orbital potential method (SAOP), the redox potentials of the molecules have been estimated and found to be in good agreement with the experimental data. An evident correlation between the molecular geometry and the electrochemical potential of the first oxidation exists and shows that, for equal number of para-conjugated triarylamine moieties, the starburst configuration is more efficient than the linear one in lowering the oxidation potential and that the amine moieties of the inner sphere play a more important role than those of the outer sphere. Besides, amine moieties connected by a biphenyl bridge show generally higher ionisation potentials than those connected via one phenylene.

Voltammetric and spectrophotometric measurements, in connection with other experimental evidences, revealed a normal oxidative behaviour of Poly(3,3??-dipentoxy-3?-dicyanoethenyl-2,2?:5?,2?terthiophene) (PolyCN) films, but a special reductive comportment, which can be summarised in the trapping of the negative charge achieved during the cathodic scan. Another interesting property of PolyCN films is the tendency to form strong intramolecular (or intermolecular) associations, probably also CT complexes. These properties could account for the failure to improve the photovoltaic performance when PolyCN was engaged in a blend formation with a polythiophene donor.Voltammetric and spectrophotometric measurements, in connection with other experimental evidences, revealed a normal oxidative behaviour of Poly(3,3??-dipentoxy-3?-dicyanoethenyl-2,2?:5?,2?terthiophene) (PolyCN) films, but a special reductive comportment, which can be summarised in the trapping of the negative charge achieved during the cathodic scan. Another interesting property of PolyCN films is the tendency to form strong intramolecular (or intermolecular) associations, probably also CT complexes. These properties could account for the failure to improve the photovoltaic performance when PolyCN was engaged in a blend formation with a polythiophene donor.