Structure-sensitive materials, or the so-called "smart materials", which change their properties under the action of external
fields (e.g. electric, light or temperature field) can find a wide use in various industrial applications as sensors, measuring elements of
various types, radiation detectors, membranes, etc. In this connection, we have examined the conditions of formation of
electrosensitive films based on copolymers of vinyledene fluoride (VDF) with tn- and tetrafluoroethylene. The films have been
prepared from solutions in organic solvents (acetone, dimethyl sulfoxide (DMCO), dimethyl formamide (DMFA) and ethyl acetate).
Based on the results of investigations of the temperature dependencies of the dielectric permittivity, surface charge density and tangent
of dielectric losses, we have evaluated the effect of film formation conditions and a copolymer type on the molecular mobility,
formation of electrets and charge relaxation in the temperature range 20-200 °C.
It has been concluded that in the non-orientated films there exists a relationship between the charge relaxation and the
molecular mobility of the C-F dipoles in amorphous and crystalline regions of the polymer matrix. At the same time, the charge
relaxation in orientated materials occurs in the crystalline regions of the polymer matrix. The optimal conditions have been specified
for the production of such materials from solutions in organic solvents.