## 4 Discussion  
With regard to the tensile test results, PDMS and SE show different performances at different ratios of base to curing agent. The suggested ratios are \(10/1\) for PDMS and \(5/5\) for SE. The elastic modulus increased dramatically with decreasing thickness. This finding is consistent with a previous study [19]. The phenomena of stretching, breaking, and deformation are critical in that the arrangement of polymer in PDMS controls its mechanical properties. The SE \(10/12\) ratio was consistently lower compared with the other SE samples due to lower base-to-catalyst ratio and thicker sample. Therefore, part A (base-to-catalyst ratio) was found to be a fundamental property for the strength of a sample. Overall, as observed in the SE graph, the lower the amount of part A (catalyst-to-base ratio), the more likely it becomes unstable. Nevertheless, there is a slight difference concerning the impact of the curing agent on the material properties. This finding is consistent with earlier studies in which the sample was mixed with higher amounts of curing agent [12,20]. In addition, a higher amount of base reduces the strength of the overall compound properties due to the lack of interaction between the base and the curing agent [20]. According to [PERSON] (Tampa, Florida), increasing the amount of cross-linker by up to 20% could stiffen the PDMS network [12]. However, other reports showed that for \begin{table}
\begin{tabular}{c c c} \hline \hline
**Energy** & **Mass Attenuation** & **Effective Atomic** _Number_ \\
**MeV** & **Coefficient (MAC)** & **(\(Z_{\text{eff}}\))** \\  & **cm\({}^{2}\)/g** & **(\(Z_{\text{eff}}\))** \\ \hline \(1.50\times 10^{-2}\) & 4.603 & 11.41 \\ \hline \(2.00\times 10^{-2}\) & 2.050 & 10.35 \\ \hline \(3.00\times 10^{-2}\) & 0.738 & 8.02 \\ \hline \(4.00\times 10^{-2}\) & 0.417 & 6.38 \\ \hline \(5.00\times 10^{-2}\) & 0.300 & 5.45 \\ \hline \(6.00\times 10^{-2}\) & 0.246 & 4.93 \\ \hline \(8.00\times 10^{-2}\) & 0.198 & 4.45 \\ \hline \(1.00\times 10^{-1}\) & 0.176 & 4.26 \\ \hline \(1.50\times 10^{-1}\) & 0.149 & 4.10 \\ \hline \(2.00\times 10^{-1}\) & 0.135 & 4.05 \\ \hline \(3.00\times 10^{-1}\) & 0.116 & 4.02 \\ \hline \(4.00\times 10^{-1}\) & 0.103 & 4.01 \\ \hline \(5.00\times 10^{-1}\) & 0.094 & 4.01 \\ \hline \(6.00\times 10^{-1}\) & 0.087 & 4.01 \\ \hline \(8.00\times 10^{-1}\) & 0.076 & 4.00 \\ \hline \(1.00\times 10\) & 0.069 & 4.00 \\ \hline \(1.50\times 10\) & 0.056 & 4.01 \\ \hline \(2.00\times 10\) & 0.048 & 4.02 \\ \hline \(3.00\times 10\) & 0.039 & 4.08 \\ \hline \(4.00\times 10\) & 0.034 & 4.15 \\ \hline \(5.00\times 10\) & 0.030 & 4.22 \\ \hline \(6.00\times 10\) & 0.028 & 4.30 \\ \hline \(8.00\times 10\) & 0.025 & 4.46 \\ \hline \(1.00\times 10^{1}\) & 0.023 & 4.62 \\ \hline \(1.50\times 10^{1}\) & 0.021 & 4.97 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Radiation attenuation properties of PDMS \(10/1\). higher concentrations of curing agent, the modulus is reduced since the cross-link sites are saturated, and excess curing agent leads to a void or dilution of the network. This reduces the stiffness, especially when measured in tension, which is inconsistent with the results of the present study, where a higher amount of curing agent reduced the elastic modulus of PDMS and SE. The density of PDMS was 0.965 g/cm\({}^{3}\), which is similar to the mass density of the kidney, 1.066 g/cm\({}^{3}\). The flexibility and stable mechanical properties of PDMS are beneficial for phantom storage and transportation. There is an apparent difference between the PDMS and SE samples. The dielectric result can be varied with different amounts of base and curing agents. In this study, the dielectric constant \(\epsilon^{\prime}r\) was lower than that of water but higher than the dielectric constant \(\epsilon^{\prime}r\) of other polymers [21]. Our thick samples might not dry fully, and this will dramatically alter the desired dielectric properties [21].