# Doped Epoxy Resins as an Alternative to Luminescent Optical Sensors
## 3 Results and Discussion
### Thermal and Spectroscopic Analysis
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \multirow{2}{*}{**Sample**} & \multicolumn{4}{c}{**Temperature at Mass Loss/C**} & \multicolumn{4}{c}{**DTG\({}_{\text{max}}\)\({}^{f}\)C**} & \multicolumn{4}{c}{**DSC\({}_{\text{max}}\)\({}^{f}\)C**} & \multirow{2}{*}{**Residual Mass/wt.\%**} \\ \cline{2-2} \cline{5-12}  & **1/wt.\%** & **3/wt.\%** & **5/wt.\%** & **I** & **II** & **III** & **IV** & **I** & **II** & **III** & **IV** \\ \hline Sample No.1-15 & 125.5 & 188.0 & 230.0 & 166.0 & 230.8 & 349.0 & 438.5 & 113.4 & 231.4 & -* & 400.9/435.3/ & 13.2 \\ Sample No.1-30 & 120.6 & 164.3 & 199.7 & 147.7 & 235.4 & -* & 439.6 & 123.6 & 234.2 & -* & 400.6/434.0/ & 10.7 \\ Sample No.1-60 & 112.2 & 156.7 & 198.4 & 148.7 & 237.1 & -* & 434.3 & 124.1 & 232.5 & -* & 406.9/431.6/ & 12.3 \\ \hline Sample No.2-15 & 111.6 & 177.6 & 221.8 & 137.6 & 242.3 & -* & 437.4 & 127.0 & 240.0 & -* & 399.3/437.9/ & 448.0 & 9.6 \\ Sample No.2-30 & 109.2 & 150.6 & 180.9 & 133.2 & 236.6 & -* & 437.4 & 121.2 & 239.5 & 334.1 & 400.7/432.1/ & 9.7 \\ Sample No.2-60 & 127.1 & 172.2 & 207.3 & 138.9 & 238.6 & -* & 438 & 124.8 & 241.0 & 343.1 & 396.9/429.1/ & 10.1 \\ \hline Sample No.3-15 & 147.3 & 192.9 & 222.2 & -* & 233.6 & -* & 439.1 & -* & 232.1 & -* & 394.4/434.2/ & 12.1 \\ Sample No.3-30 & 105.0 & 146.6 & 178.9 & 132.5 & 235.5 & -* & 437.6 & 118.9 & 234.0 & -* & 393.9/431.7/ & 10.9 \\ Sample No.3-60 & 116.9 & 155.9 & 187.5 & 136.8 & 229.9 & -* & 436.9 & 120.3 & 233.3 & -* & 431.1/441.7 & 13.0 \\ \hline Sample No.4-15 & 102.3 & 139.6 & 168.7 & 134.3 & 188.4 & 242.6 & 431.5 & 129.3/ & 240.6 & 322.6/ & 429.3 & 8.8 \\ Sample No.4-30 & 96.5 & 122.5 & 170.9 & 143.6 & 187.6 & 252.4 & 432.4 & 131.2/ & 250.1 & 325.1/ & 428.3 & 10.2 \\ Sample No.4-60 & 92.8 & 117.1 & 170.8 & 137.5 & - & 237.3 & 431.5 & 127.1 & 255.2 & 352.8 & 428.4 & 10.2 \\ \hline Sample No.5-15 & 92.6 & 134.2 & 156.4 & -* & 185.4 & -* & 436.7 & 132.7 & 273.6 & 333.5 & 431.7/444.5 & 9.7 \\ Sample No.5-30 & 98.7 & 137.5 & 159.6 & -* & 172.0 & -* & 436.1 & 130.1 & 279.0 & 345.8 & 414.7/429.7/ & 10.0 \\ Sample No.5-60 & 101.2 & 140.0 & 164.1 & -* & 193.3 & -* & 436.4 & 127.9 & 278.5 & -* & 427.9/436.4 & 8.2 \\ \hline \end{tabular}
\end{table} 
Table 4: Temperature characteristics based on TG/DTG and DSC curves. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Sample**} & \multicolumn{4}{c}{**Temperature at Mass**} & \multirow{2}{*}{**DTG\({}_{\text{max}}\)/\({}^{c}\) C**} & \multicolumn{4}{c}{**DSC\({}_{\text{max}}\)/\({}^{c}\) C**} & \multicolumn{4}{c}{**Residual**} \\ \cline{2-13}  & \multicolumn{2}{c}{**Loss/\({}^{c}\)C**} & \multicolumn{2}{c}{**DTG\({}_{\text{max}}\)/\({}^{c}\) C**} & \multicolumn{4}{c}{**DSC\({}_{\text{max}}\)/\({}^{c}\) C**} & \multicolumn{4}{c}{**Mass/wt.\%**} \\ \cline{2-13}  & **I/wt.\%** & **3/wt.\%** & **5/wt.\%** & **I** & **II** & **III** & **IV** & **I** & **II** & **III** & **IV** & \\ \hline Sample No.6-15 & 95.7 & 134.2 & 166.3 & 140.2 & -* & 235.8 & 432.5 & 130.3/ 160.7 & 243.2 & 323.0/ 160.7 & 430.2 & 9.9 \\ Sample No.6-30 & 85.4 & 135.6 & 163.0 & 138.1 & -* & 230.0 & 432.8 & 122.0/ 174.2 & 239.2 & 322.2/ 150.8 & 430.2 & 10.0 \\ Sample No.6-60 & 100.4 & 145.8 & 175.9 & 141.8 & -* & 231.2 & 433.2 & 128.9/ 162.3 & 235.3 & 321.5/ 162.3 & 431.0 & 9.1 \\  
Analyzing the data for compositions based on EB150 resin with 25 wt.% NVP addition (samples No.1, No.2 and No.3), it can be concluded that the increase in exposure time does not significantly affect the improvement of thermal resistance. For samples No.1-15, No.1-30 and No.1-60, a noticeable mass loss (around 1 wt.%) was recorded around 120 \({}^{\circ}\)C, although the temperature values obtained for the sample exposed to 15 s of light are slightly higher. The same applies to the DTG curve values. The fact that 3-4 maxima are recorded on the DTG and DSC curves proves the complexity of the composite structure. The presence of one maximum (at the highest temperature) is obviously related to the proper decomposition of the sample.