Composite films made of poly(vinylidene fluoride) (PVDF) and conducting particles of carbon black (CB) were prepared using a hot press. Using different volume fractions of CB filler, electrical properties of the samples were analyzed with current-voltage (I 9 V) measurements and impedance spectroscopy. To help the discussion, percolation theory and simulation circuits based on Colie diagrams were used. The percolation threshold was found at 3 vol% of CB. At these volume fractions of filler, scanning electron microscopy (SEM) images showed connected particles in the polymer matrix, while in the higher volume content of filler, the particles started to form clusters. Furthermore, it was observed that increasing volume fractions up to 3 vol%, the Young's modulus and the tensile strength of the composite film were higher than that of the pure polymer, although the rupture strain was decreased. Composite films with 3 vol% of CB showed optimized electrical and mechanical properties and may be useful as an electrostatic dissipater.

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Films made of a blend of polyaniline (PAni) and a nonpolar polyvinylidene fluoride (PVDF) polymer matrix were obtained by the mechanical mixing of both, with subsequent melting and quenching. Using the current versus voltage (IxV) measurements, the percolation threshold (concentration in which some conducting particles are connected to form at least one conductor path, related to one direction of the film) was determined to be between 40 and 45 % in volume along the surface. Related to the film thickness, a small amount of PAni (0.5 % in volume) was enough to transform the blend in a conducting material. Strain-stress tests indicated that a small amount of PAni can reinforce the polymer matrix. Furthermore, the immiscible blend obtained changes in its electrical conductivity, according to the pH of the solution in which it was immersed, indicating the possibility of the real application of that material as a resistor with variable electrical resistance.