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The research of electric properties of the systems based on polyethylene glycol and carbon nanotubes (CNT) near-by the percolation threshold is done using the method of impedance spectroscopy. It is set that the percolation threshold for these systems substantially depends on the sizes of nanotubes. It is discovered that with the increase in the CNT diameter, the percolation threshold is increased. The dispersion parameters of nanotubes were calculated using theoretical model. The results of calculations and microphotographs testify to the high level of CNT aggregates in the polymer nano-composites based on polyethylene glycol. [ABSTRACT FROM AUTHOR]

Experimental results and theoretical studies of thermophysical characteristics crystalline polyethylene nanocomposites containing from 0.3 to 2.5 wt. % carbon black and nanocomposites containing from 0.2 to 1.5 wt. % carbon nanotubes is done in the article. The fundamentals of the effective medium theory and percolation theory and how they correlate with the experimental data is shown. The features of the structure's influence of polymer composites on their thermal properties is studied. A comparative analysis of the thermal conductivity of the compositions according to the geometry of the filler is done. [ABSTRACT FROM AUTHOR]

The research of the electrical properties of the systems based on polyethylene glycol and carbon nanotubes near-by the percolation threshold is done using the method of impedance spectroscopy. It is established that the percolation threshold for these systems is 0,5%, and critical index t = 1,17. It is discovered that non-conducting polymeric film appears between separate nanotubes. The thickness of the film which is 7-8 Å and its contact resistance which is 3·105 Ohm were derived using theoretical models. This explains a difference in conductivity of pure nanotubes and probed system after the percolation threshold. [ABSTRACT FROM AUTHOR]

The investigation of electric and dielectric properties of the systems based on polypropylene glycol and carbon nanotubes, which contain inorganic salt LiClO4 and without salt, was conducted using the method of impedance spectroscopy. It was discovered that these systems show a fractal behavior. The percolation thresholds of the probed systems is determined, it is 0.45% and 0.40%, accordingly. It was set that the processes of charges transfer are described well within the framework of the model of intercluster polarization. For the system PPG-LiClO4- CNT the so-called, "bridge" effect takes place which leads to the decrease of the prcolating threshold. [ABSTRACT FROM AUTHOR]

Structure and percolative properties of composites based on polyvinyliden fluoride (PVDF) and its mixtures with polyaniline (PANI), doped with p-toluenesulfonic acid (TSA) was investigated by the methods of X-ray analysis, differential scanning calorimetry and impedance spectroscopy. It was shown, that descriptions of such compositions substantially depend on content of PANI-TSA and on the method of their preparation. It was established, that systems PVDF-PANI-TSA show a percolation behavior with low percolation threshold Cc H" 4%. The decrease of the crystallinity of PVDF-PANI-TSA systems specifies the mobility decrease of polymer chains of PVDF in the boundary layer around particles PANI-TSA. The investigated system is incompatible, that results in a segregation PANI-TSA in a separate phase. [ABSTRACT FROM AUTHOR]

The development, structure and properties of polymer electrolytes were discussed in the review. The special attention was spared to the influence of fillers on structural descriptions, electric and thermophysical properties of nanocomposite polymer electrolytes. The data of conductivity and temperatures of transitions for the described systems were cited. [ABSTRACT FROM AUTHOR]

By using Fuoss-Kraus theory and the conductivity data, we study the ion association in polymer electrolyte based on polyethyleneglycol, lithium perchlorate and carbon nanotubes. We also determine that the filler addition decreases the aggregation in the polymer electrolyte, which leads to the increase in the number of free ions, as well as to the conductivity growth. [ABSTRACT FROM AUTHOR]

Structure and thermal properties of systems based on olygoethyleneglycol and anisometric nanofillers were studied using X-ray scattering and DSC methods. It is shown that structure and thermal properties of the systems based on OEG substantially depend on the nature and content of nanofiller. It is discovered that thermal characteristics has extreme behavior, which is dependent on composition of systems based on OEG. [ABSTRACT FROM AUTHOR]

The relaxation processes and conductivity of polymer electrolytes based on oligoethyleneglycol (OEG) and anisometric nanofillers were studied using dielectric relaxation spectroscopy. It is shown that the levels of conductivity of the systems based on OEG substantially depend on the nature and content of nanofiller. It is discovered that conductivity of direct current has extreme dependence on composition of polymer electrolytes based on OEG. [ABSTRACT FROM AUTHOR]

Hyperbranched polyetherurethanes were synthesized by the reaction of Hyperbranched aliphatic polyeterpolyols of three generation and isocianate forpolymers. Synthesized polymers were characterisated by the method of IK-spectrums, IPS-chromatography, different scanning calorimetric. That were found that the urethanes fragments in the chain lead to the microgeterogenic structure of hyperbranched polymers. [ABSTRACT FROM AUTHOR]

Properties of new film-forming nucleus-fluorinated aromatic polyethers comprising tertiary and quaternary atoms of nitrogen (in the form of salts) have been investigated. Introduction of specified nitrogen atoms into polymers, alongside with change in the aminoalkyl fragment chemical construction, allows to control their mechanical and physico-chemical features in a wide range. Ammonium salts were successfully transformed into polymeric ammonium basis, static ion-exchange capacity of which is not lesser than that of sulfonated fluorocontaining aromatic polyethers. [ABSTRACT FROM AUTHOR]