Abstract <p>The article discusses the changes occurring in polypropylene and its compositions with silicon dioxide, which occur under the influence of electro-thermal polarization. The dependence of the piezoelectric properties of polypropylene compositions on the percentage of the additive has been revealed. The present study identifies the dependence of the piezoelectric properties of polypropylene compositions on the percentage content of the additive. Furthermore, it demonstrates that the dependence of the charge of polymer compositions of polypropylene with silicon dioxide on the filler content can be described by an exponential curve with a peak at 3% filler content. Furthermore, the quasi-static piezoelectric coefficient of polypropylene compositions with 3% silicon dioxide has been examined in relation to both preload and the spectrum of thermally stimulated depolarization of the composite.</p>