Study on the electrical properties of nanopaper made from nanofibrillated cellulose for application in power equipment.

This study aims to evaluate the suitability of using nanopaper as an insulating material since it has outstanding mechanical and thermal properties. Nanopaper consisting of nanofibrillated cellulose was prepared. Properties of ordinary insulating paper were taken as a reference. DC volume resistivity results show that nanopaper can obtain a relatively high value of 2.55 × 10¹² Ω m, which will be more compatible with mineral oil. In spite of the lower density, nanopaper tends to have a higher complex relative permittivity than reference paper. Due to the decreased pore size, nanopaper presents a remarkably enhanced DC breakdown strength. The dielectric strength of nanopaper can reach 69.4 kV/mm, whereas that of ordinary kraft paper is only 20.4 kV/mm. It is concluded that nanopaper has good electrical properties. The decreased volume resistivity and dramatically enhanced breakdown strength indicate that the potential application of nanopaper in convert transformers is promising. [ABSTRACT FROM AUTHOR]