부산대학교 도서관

This paper presents preparation of composites consisting of alicyclic epoxy resin and carbon black (CB), and investigation on the effect of CB addition rate $R_{\text{cb}}$ on dielectric breakdown strength ($E_{\mathrm{b}}$). Experimental results showed that $E_{\mathrm{b}}$ decreased with increasing $R_{\text{cb}}$, even by less than half of that of the sample without CB addition when $R_{\text{cb}}$ further increased from 0.1 wt% to 0.5 wt%. Observation using a digital microscope showed that the CB in the sample was not well dispersed: the particle size of CB alone was on the order of nanometers, while many agglomerates of several tens of microns were observed. As a result, the decrease in $E_{\mathrm{b}}$ due to the CB addition is considered to be closely related to the size and number of CB agglomerates.