Electrical Properties Studies of a Cork/TetraPak®/Paraffin Wax Composite

Lately the electrical and dielectric properties of cork and sorne cork-based materials (commercial and non-commercial)have been studied in order to understand their ability to store clectrical charge. The main problem found so fal' is related to the water content in cork, only of a few (porcent)weight, but large enough to influence greatly the conductivity of cork and, consequently, the charge storage capability. To overcome this problem cork has been combined with hydrophobic materials. In this work a commercial wax (paraffin wax)was used to produce a corklparaffin composite by hot pressing. After mil1ed and mixed natural cork, TetraPak® containers waste and paraffin were pl'essed to make plaques of a new composite. Different concentrations of cork, TetraPak® and paraffin, different granules size, different temperature and pressure were used to produce tbe samples. The electrical properties of the new composite were measured by the isothermal charging and discharging current method and the results compared to previously ones obtained for natural cork and other derivative products. The new composite has shown to have lower conductivity than the commercial agglomerate, which makes it a better material for charge storage.