Electrical and Optical Properties of Polyvinyl Chloride–Polyacetylene Copolymer

Technical Physics - The temperature dependence of the conductivity of heat-treated polyvinyl chloride films containing conjugated double carbon–carbon bonds in the chain of its macromolecules...     

Properties of Silver Nanoparticles in the Presence of Dysprosium

Technical Physics - Various methods of binding rare-earth metal ions with nanoparticles make it possible to obtain materials with new properties. The “green” synthesis method has been...     

Anomalies and error limits in electrical-conductivity measurements in plasticized transparent poly(vinyl chloride) films

The anomalous behavior of the electrical conductivity of transparent poly(vinyl chloride) films is experimentally studied at field voltages approaching the breakdown threshold, above the threshold, and far below the threshold. The effects of strong nonlinearity, relaxation drifts, and spontaneous reversible transitions between states with high and low electrical conductivities are revealed for the first time in “thick” (20–100 μm) plasticized transparent poly(vinyl chloride) films. When a certain threshold is exceeded, relaxation oscillations in the test sample are generated and their frequency is proportional to the applied voltage. During a “mild” breakdown, the polymer film passes into the high-conductivity state (the current increases by four or more orders of magnitude), which is identical to the states observed during low-voltage transitions. A simple qualitative model explaining the anomalous character of the electrical conductivity of plasticized poly(vinyl chloride) films is advanced.     

Switching of the electrical conductivity of plasticized PVC films under uniaxial pressure

The jumplike switching of the electrical conductivity in wide-band-gap polymer (antistatic plasticized polyvinylchloride) films under uniaxial pressure is studied. In various plasticized PVC materials, the uniaxial pressure inducing a conductivity jump by four orders of magnitude or higher changes from several to several hundreds of bars, and this effect is retained at a film thickness of several hundred microns, which is two orders of magnitude larger than the critical film thicknesses known for other wide-band-gap polymers. In addition to the earlier interpretation of the conductivity anomalies in plasticized PVC, we proposed a phenomenological electron-molecular dynamic nanotrap model, in which local charge transfer is provided by mobile molecule segments in a plasticized polymer.     

Analysis of the properties of dehydrochlorinated polyvinyl chloride films

The effect of the time of thermolysis (thermal degradation) on the absorption spectra, specific resistivity, and concentration of holes of partially dehydrochlorinated polyvinyl chloride films has been studied. The number of conjugated carbon double bonds in films has been determined as a function of the time of thermolysis.     

Effective Medium Approximations for the Description of Multicomponent Composites

Technical Physics - We compared several generalizations of the Bruggeman effective medium approach with the use of elliptical cells. Namely, a “uniaxial” anisotropic approximation and...     

Synthesis of composites with alternating layers of poly(vinyl chloride) and single-wall carbon nanotubes homogeneously dispersed in carboxymethyl cellulose

For preparation of water-resistant and thermally stable nonlinear optical elements containing single-wall carbon nanotubes, an original method for the formation of layered structures based on alternating layers of poly(vinyl chloride) and a water-soluble polymer (carboxymethyl cellulose) with dispersed singlewall carbon nanotubes is proposed. An analysis of the optical properties of the resulting composites by means of optical-absorption spectroscopy and Raman scattering makes it possible to confirm that the nanocomposites contain individual (not united in bundles) single-wall carbon nanotubes.