Structural changes proceeding in composites under the effect of various mechanical deformations (stretching, compression, shear, etc.) affect the structure of an electrical conducting system. Mechanical stresses, induced by deformation of composite materials during deformation, affect both the molecular and supermolecular structure of polymers. As a consequence, they also affect a substructure bound to it and composed of filler particles. It is evident that in the case of conducting polymer composites, mechanical deformations should reflect electric conductivity of materials. Key words: mechanical deformations; macromolecules; electric conductivity; polymers ELECTRIC CONDUCTIVITY OF CARBON BLACK-FILLED RUBBERS UNDER STRETCHING DEFORMATIONSMechanical deformations that initiate intertransformations of macromolecules can affect the topology of conducting particles interacting with macromolecules. Many works have studied connections between structural features of composites and their electric conductivity at deformation.

On the basis of mixes of phenolformaldehide and epoxy resins at the presence of some silicon organic compounds and fiber glasses annealed in vacuum and hydrogen media the new conductive monolithic materials have been created. Conductive, magnetic and some other properties of these materials were investigated. It was established experimentally that the obtained products are characterized by semiconductive properties, the level of conductivity and conductive type of which are regulated by selection of technological methods. The density and mobility of carriers increase at increasing of annealing temperature up to definite levels. The temperature dependence of the electrical conductivity and charge mobility were described by Mott formulas. The magnetic properties of the annealed materials were investigated by ESR method. It was established that at annealing free radicals and other paramagnetic centers are formed. On the basis of the obtained results it was proposed that formation of conducting clusters and the charge transport between them is provided by mechanism of charge jumping with alternative longevity of the jump.

The role of the structural peculiarities of electrical conducting polymer composites (ECPC) has been considered. Different conception on the nature of the conductivity, the mechanisms of charge transfer in heterogeneous structures are presented in this review. Experimental results obtained by different scientists are only partially in concordance with existing theoretical models. It is suggested that missing of various physical and chemical factors influencing the processes of electrical current formation in polymer composites is one of the main reasons of the mentioned divergence between theory and experimental results among which the rate of the values of inter-and intra-phase interactions in composites may be considered as a very important factor. The peculiarities of dependence of the conductivity of systems with binary conducting fillers are considered in this work as well.

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Much sawdust is treated as waste and deposited in landfills; with time, the city landfills have to be made larger and larger and/or deeper and deeper. We have created composites on the basis of dry sawdust and only 3 wt% to 15 wt% of phenylethoxysiloxane binders of two kinds under pressures up to 15 MPa and temperatures up to 220 C. Hot pressing of one of the composites containing 3 wt% of one of the polymeric binders at 110 C provides the impact viscosity = 12 kJ/m 2 while the pressing at 200 C results in the value of that viscosity = 30 kJ/m 2. Another option is using 5 wt% of the same polymer at 110 C what gives the impact viscosity = 20 kJ/m 2. Water absorption after 24 hours exposition in water for 15 wt% of the same polymer amounts to 55.5 wt% when the composite is prepared at 130 C but only 2.9% for the composite made at 170 C. Given low-to-negligible prices of sawdust, composites with useful properties and low prices can be made from it-along with mitigation of waste creation.