## 3 Results
To observe the biodegradable ability of the samples, we immersed the samples in the SBF solution, and the data was taken at the 1 st, 3 rd, and 4 th weeks. As shown in Figure 4, the CMC strongly affects the biodegradable ability of the samples, wherein, the increase of CMC content can increase the percentage of weight loss. We speculate that this is due to the fact that both Ch and CMC are hydrophilic, and generated a degradation from the hydrolysis process when the samples were  
Figure 3: The surface (**a–e**) and cross-sectional (**f–j**) SEM results of the nanocomposite-based scaffold n-HA/Ch/CMC, having average pore sizes of \(\sim\)100 \(\upmu\)m.  
Figure 2: The porosity (**black line**) and compressive strength (**blue line**) of nanocomposite-based scaffold n-HA/Ch/CMC. immersed in SBF solution. The weak C-O bonding (reactive) in the CMC is easy to break when they interact with molecules from the SBF solution. It is worthwhile to mention that the nanocomposite-based scaffold n-HA/Ch/CMC should be bioactive, biodegradable, containing 30-90% porosity, and require a minimum compressive strength of 2 MPa. According to the compilation data made in Table 2 and the literature study, we conclude that sample C, with 10 wt% of CMC, is considered as the best sample. This sample contains 49.77% porosity, the compressive strength of 3.89 MPa, percent of weight loss at the 4 th week of about 29.92%, nearly constant degradation rates, and average porosity sizes of about 92.10-136.00 \(\upmu\)m. In this case, the CMC gives a significant impact on the quality of the scaffold, wherein it has a pivotal role to control the porosity and mechanical strength of the composite-based scaffold. After realizing the scaffold with desirable porosity and mechanical strength for BTE application, we also analyzed the thermal properties of this nanocomposite-based scaffold. Here, we used DSC measurement to determine the steam temperature (Tb), glass transition temperature (Tg), decomposition temperature (Td), and crystallization temperature (Tc) at temperature ranges of 25-900 \({}^{\circ}\)C, as shown in Figure S1 of the supporting material. We compiled the observed data we obtained in DSC measurements, as shown in Figure 5. We found that the Tb, Td, and Tc tend to increase with increasing CMC, conversely, the Tg tends to decrease with increasing CMC. As previously explained, Ch has opposite charge with CMC, which forms an ionic bonding and induces a cross-link between them [18]. Henceforth, the CMC enhances the chemical bond of n-HA and Ch, generating the reduction of porosity and enhancing the \begin{table}
\begin{tabular}{c c c c c c c} \hline \multirow{2}{*}{**Parameters**} & \multicolumn{6}{c}{**CMC Variations**} \\ \cline{2-7}  & **A (0 wt\%)** & **B (5 wt\%)** & **C (10 wt\%)** & **D (15 wt\%)** & **E (20 wt\%)** \\ \hline Porous diameters (\(\upmu\)m) & 24.80–136.00 & 46.10–155.00 & 92.10–136.00 & 25.46–150.10 & 26.82–177.30 \\ \hline Porosity (\%) & 85.92 & 61.72 & 49.77 & 44.65 & 37.51 \\ \hline Compression strength (MPa) & 1.49 & 1.57 & 3.89 & 4.14 & 5.47 \\ \hline \multirow{2}{*}{
\begin{tabular}{c} Percent weight \\ loss (\%) \\ \end{tabular} } & First week & 4.66 & 18.49 & 22.90 & 35.40 & 31.60 \\ \cline{2-7}  & Third weeks & 10.91 & 20.94 & 27.37 & 36.82 & 34.61 \\ \cline{2-7}  & Fourth weeks & 11.60 & 21.70 & 29.92 & 37.31 & 35.61 \\ \hline \end{tabular}
\end{table} 
Table 2: Compilations of porosity, mechanical strength, and biodegradability data from experiments. Figure 4: Percentage of weight loss of nanocomposite-based scaffold n-HA/Ch/CMC taken in the 1 st, 3 rd, and 4 th weeks. mechanical strength. In this sense, it may be required a higher thermal energy to perturb the molecules in the samples with higher CMC composition. Therefore, this leads to the variation of steaming ability (Tb), chemical decompositions (Td), and crystallization (Tc) of the samples with a variation of CMC composition.