Electrical properties of polyurethane-based composites

In this study the effect of nano size borax fillers in polyurethane is investigated by evaluating its electrical properties; the relative permittivity, loss factor and dc conductivity. The particle size of borax fillers used in this study is 70 nm. The borax filler/TPU composites were prepared with 1% by weight of filler content. Evaluation of conductivity, loss factor and dielectric constant is performed using a high voltage testing kit. For evaluating the conductivity of the material, high voltage dc source was used, while for determining the dielectric constant and loss factor a high voltage ac source operating at 60 Hz was employed. The nanocomposite with 70 nm particle size and a concentration of 1% by weight borax filler indicated a lower dc conductivity and relative permittivity than of pure TPU. The measured value of loss factor is higher than that of pure TPU samples.