Dielectric strength of glass fibre fabric reinforced epoxy by nano-Al<sub>2</sub>O<sub>3</sub>
Shuang Wang, Yu Chen, Jiale Mao, Cong Liu, Lei Zhang, Yonghong Cheng, Chaoyun Du, Toshikatsu Tanaka
Abstract
Filling epoxy resin in glass fibre fabric with surface modified nano-Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> as a means of increasing the dielectric strength is investigated in this work. The 50 Hz breakdown strength with 3 wt% nano-Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> is shown to be 10% higher than the neat epoxy/glass fibre material and 4% higher than the neat epoxy. An improved interface bonding between the glass fibre and the epoxy is evidenced by SEM characterization. Based on a multilayer dielectric model, it is found that introducing nano-Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> to the epoxy resin can efficiently alleviate the dielectric constant mismatch between the epoxy and the epoxy-integrated glass fibre layer, which results in an improvement in the dielectric strength.