Igors Klemenoks

Investigation of mechanism of organic solvent vapours sensing effect in polyisoprene-high structure carbon black composite

A study of detecting organic vapour environments of nine different solvents by polyisoprene-high structured carbon composite (PHSCBC) sensors is reported. The electric resistance of the composite is found to be increased as soon as it contacts the vapour and to return to the initial value after being removied from the environment. To reveal the mechanism of the effect, simultaneous measurements of electrical resistance, elongation, and changes caused by sorption of organic solvent molecules in the bulk of PHSCBC samples were made in real time. From sorption experiments it has been found that the increase of electric resistance is generally dominated by absorption of solvent molecules in the matrix material, subsequently swelling it up and increasing the distance between conductor particles. The experiments prove that a remarkable and rapid change of the resistance could be explained by change of the tunnelling currents between adjacent carbon nano-particles.

Nanostructure carbon black-polyisoprene composites as prospective strain sensor materials: macro- and nanoscale studies

Nanostructured carbon black-polyisoprene composite is prepared and investigated. A giant reversible tensoresistive effect -- dependence of electrical resistance vs. uniaxial tension deformation - is found. A new application of the conductive atomic force microscope for the carbon black network mapping in a nonconducting matrix is reported.