Effect of boron nitride on delamination phenomenon and performance of lightweight epoxy potting materials

Abstract The aerospace field requires spacecraft to develop in the direction of lightweight. The filler delamination phenomenon in the lightweight epoxy potting material was solved by doping with micron boron nitride (BN), and the changes of filler distribution uniformity, thermal conductivity, electrical properties, and mechanical properties of the epoxy composites with the doping amount of micron boron nitride were investigated. The results showed that the addition of BN solved the delamination phenomenon of the epoxy system, and the overall density of the system increased slightly when the mass fraction of BN doping was 4%, but the density difference of the system decreased from the initial 0.334 g/cm 3 to 0.015 g/cm 3 , with a decrease of 95.5%. It was found by scanning electron microscopy that the glass beads were more uniformly distributed in the matrix. In addition, the addition of BN effectively enhanced the thermal conductivity of the composites, which reached a maximum value of 0.819 W/(m·K) when the mass fraction of BN was doped at 3%, and both the IF dielectric constant and dielectric loss factor of the composites decreased and then increased with the filler content. The IFC and dielectric loss factors of the composites both decreased and then increased with the increase of filler content, while the volume resistivity increased and then decreased, but remained at 10 14 orders of magnitude. The addition of boron nitride affects the mechanical properties of the material, but the degree of change is not significant, and the material still has good impact and tensile properties.