## 3 Results and Discussion
### Dielectric Properties of GO/AMT-CE Composites  
The dielectric test was carried out by the Agilent 4294A at a frequency of 400 HZ to 20 MHz under room temperature. The results are shown in Figure 7 and Table 3. It can be observed from Figure 7 that the dielectric constant of GO/AMT modified CE resin was smaller than that of pure CE resin. At the same time, the dielectric constant decreased with the increase of GO/AMT in CE resin. GO is an insulator, with oxygen atoms randomly attached on graphene sites, which undergo conversion from sp2-hybridized carbon atoms in graphene to sp3-hybridized carbon in GO. In addition to exhibiting low Dk values for these materials, GO sheets are used as interlayers in the polymer matrix because the GO homogeneity is not as great as that of graphene, hence, there is much less electron mobility. This process reduces conjugation and confines p-electrons [47], resulting in very low-dielectric constant values of GO. For example, [PERSON] et al. proposed an effective approach that used in situ polymerization to fabricate large-area GO/polyimide (PI) composite films. The results showed the bulk dielectric constant decreased from 3.3, for the neat PI film, to just 2.0 for the PI-ODA-GO composite film [48]. [PERSON] et al. reported an efficient and novel method to functionalize GO with hyperbranched polysiloxane and successfully compound them with CE resin to prepare nanocomposites. The study showed a lower and more stable dielectric constant and loss than pure CE resin over the testing frequency from 10 to 60 MHz [41]. In addition, the adamantly group that possessed a cage structure of the whole aliphatic had a lower polarization, which effectively increased the large free volume of polymer. We suggest that both polarization and free volume of polymer are crucial for the dielectric constant. For instance, the increase of the free volume and the reduction of the polarization will reduce the dielectric constant of polymer.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Content** & **Tensile Strength (Mpa)** & **Elongation at Break (\%)** & **Tensile Modulus (Mpa)** \\ \hline \multirow{2}{*}{Pure CE} & 36.3 \(\pm\) 5.0 & 2.38 \(\pm\) 0.32 & 1390 \(\pm\) 80 \\  & 32.7 \(\pm\) 4.6 & 2.18 \(\pm\) 0.27 & 1320 \(\pm\) 70 \\ \hline \multirow{2}{*}{0.3\% GO/AMT} & 44.9 \(\pm\) 5.8 & 3.37 \(\pm\) 0.28 & 1430 \(\pm\) 90 \\  & 40.2 \(\pm\) 5.3 & 2.80 \(\pm\) 0.32 & 1440 \(\pm\) 100 \\ \hline \multirow{2}{*}{0.5\% GO/AMT} & 53.8 \(\pm\) 6.7 & 3.90 \(\pm\) 0.34 & 1540 \(\pm\) 80 \\  & 49.1 \(\pm\) 5.8 & 3.22 \(\pm\) 0.29 & 1520 \(\pm\) 80 \\ \hline \multirow{2}{*}{0.7\% GO/AMT} & 58.2 \(\pm\) 5.9 & 4.30 \(\pm\) 0.31 & 1610 \(\pm\) 100 \\  & 55.7 \(\pm\) 5.2 & 4.13 \(\pm\) 0.30 & 1690 \(\pm\) 110 \\ \hline \multirow{2}{*}{1.0\% GO/AMT} & 63.1 \(\pm\) 6.1 & 4.86 \(\pm\) 0.26 & 1650 \(\pm\) 70 \\  & 58.2 \(\pm\) 5.6 & 4.65 \(\pm\) 0.28 & 1620 \(\pm\) 90 \\ \hline \hline \end{tabular}
\end{table}
Table 2: The mechanical properties of the dried and wet (upper and lower row, respectively for each material) CE resins modified by GO/AMT.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Sample** & **Dielectric Constant (at 1 MHz)** & **Dielectric Constant Decrease** & **Dielectric Loss (at 1 MHz)** \\ \hline \multirow{2}{*}{Pure CE} & 3.9465 & - & 0.0122 \\  & 3.7472 & \(-\)0.1993 & 0.0105 \\  & 3.1843 & \(-\)0.5629 & 0.0098 \\  & 2.8837 & \(-\)0.3006 & 0.0072 \\  & 2.5437 & \(-\)0.3400 & 0.0063 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Dielectric properties of GO/AMT-CE composites with different GO/AMT contents.  
In addition, good adhesion between GO/AMT and CE resin will reduce interfacial polarization and limit the mobility of the segments, resulting in the decrease of the dielectric constant. As a result, we suggest that the obtained composites be equipped with excellent dielectric property.