Electrospinning as a versatile technique producing nanofibers was employed to study the influence of the processing parameters and chemical and physical parameters of solutions on poly(vinylidene fluoride) (PVDF) fibers’ morphology, crystallinity, phase composition and dielectric and piezoelectric characteristics. PVDF fibrous layers with nano- and micro-sized fiber diameters were prepared by a controlled and reliable electrospinning process. The fibers with diameters from 276 nm to 1392 nm were spun at a voltage of 25 kV–50 kV from the pure PVDF solutions or in the presence of a surfactant—Hexadecyltrimethylammonium bromide (CTAB). Although the presence of the CTAB decreased the fibers’ diameter and increased the electroactive phase content, the piezoelectric performance of the PVDF material was evidently deteriorated. The maximum piezoelectric activity was achieved in the fibrous PVDF material without the use of the surfactant, when a piezoelectric charge of 33 pC N−1 was measured in the transversal direction on a mean fiber diameter of 649 nm. In this direction, the material showed a higher piezoelectric activity than in the longitudinal direction.

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In proposed study the effect of the composition and structure of polyurethane/ground rubber (PUR/GR) composites on the mechanical behavior was evaluated. The structure-properties relationship was studied for PUR matrices with different polarity, porosity and mechanical properties. The morphology of PUR/GR composites was expressed by two structural parameters-interspace filling and interspace volume. Experimental data of mechanical testing were fitted by powerlaw functions containing mentioned structural parameters whereas exponents of these parameters reflect differences in mechanical properties and chemical composition of PUR matrices. Obtained equations describe the mechanical behavior with respect to the structure and morphology of porous PUR/GR composites consisting of one filler and different PUR matrices. Proposed study suggests new approach to the description of the relationship between mechanical behavior and structure of porous composite materials.