# Design of SBS-Modified Bitumen Stabilizer Powder Based on the Vulcanization Mechanism
## 6 Microcosmic Test  
A fluorescence microscope was used in this paper to observe the SBS bitumen from a microcosmic view after vulcanization reaction. The principle of the fluorescence microscope is described as follows. Fluorescence will occur in a short period of time after materials are excited. Most of the polymer materials can emit fluorescence light directly after high energy luminescent beam irradiation, and a red shift interval will occur between the high energy luminescent beam and fluorescence after excitation, then the wavelength of fluorescence will become longer as visible light. Bitumen cannot produce fluorescence in the blue light region, while the yellow-green fluorescence comes from SBS. The fluorescence microscope worked on the principle above.  
Before the fluorescence microscope test, SBS-modified bitumen was prepared respectively with different stabilizers (S:TMTD:ZnO:BHT: Al\({}_{2}\)O\({}_{3}\):2 SiO\({}_{2}\):2H\({}_{2}\)O = 60:16:4:20:1250, S:TMTD:ZnO:BHT:SiO\({}_{2}\) = 60:16:4:20:625), and the stabilizer contents were both 0.09% (bitumen mass percentage, expressed as S content), while SBS content was 4% (bitumen mass percentage). SBS bitumen was put into the oven at a temperature of 163 \({}^{\circ}\)C for 48 h, sampling the upper 1/3 and the lower 1/3, respectively. Then, different SBS-modified bitumen was dropped on the glass, respectively, and the cover glass was pushed from one side to another lightly without air bubbles. The glass with bitumen was put under  
\begin{table}
\begin{tabular}{c c c c c c} \hline \multirow{2}{*}{\begin{tabular}{c} **Component** \\ **No.** \\ \end{tabular} } & \multicolumn{3}{c}{**RTFOT**} & \multirow{2}{*}{\begin{tabular}{c} **Penetration**, \\ **Reside Ductility at** \\ **Percentage, \%** \\ \end{tabular} } & \multirow{2}{*}{\
\begin{tabular}{c} **Penetration** \\ **Reside Ductility at** \\ **5\({}^{\circ}\)C** \\ \end{tabular} } & \multirow{2}{*}{
\begin{tabular}{c} **Penetration** \\ **Index PI** \\ \end{tabular} } \\ \hline
4 & 0.08 & 79.2 & 21.0 & 55.3 & 0.1 \\
29 & 0.10 & 77.2 & 19.7 & 55.0 & 0.1 \\
30 & 0.09 & 78.3 & 19.5 & 54.4 & 0.1 \\
31 & 0.12 & 78.5 & 18.7 & 54.2 & 0.1 \\
32 & 0.09 & 79.4 & 18.2 & 53.6 & 0.1 \\ \hline \end{tabular} \begin{tabular}{c} **Component** \\ **No.** \\ \end{tabular} & \begin{tabular}{c} **Ductility at** \\ **5\({}^{\circ}\)C, cm** \\ \end{tabular} & **Softening Point \({}^{\circ}\)C** & \
\begin{tabular}{c} **Brookfield viscosity** \\ **at 135 \({}^{\circ}\)C, Pa-S** \\ \end{tabular} & **Solubility, \%** &
\begin{tabular}{c} **Resilient at** \\ **25\({}^{\circ}\)C, \%** \\ \end{tabular} \\ \hline
4 & 29.6 & 78.3 & 1.973 & 99.3 & 87.7 \\
29 & 29.0 & 79.1 & 1.983 & 99.1 & 87.5 \\
30 & 28.2 & 79.3 & 1.990 & 99.1 & 87.2 \\
31 & 27.5 & 79.8 & 1.936 & 99.1 & 87.4 \\
32 & 26.3 & 80.2 & 1.998 & 98.8 & 87.3 \\ \hline \end{tabular}
\end{table}
Table 8: Performance of SBS-modified bitumen with different carbon-white content.  
the fluorescence microscope, and it was observed with a 100 and a 400 amplified factor, as shown in the Figure 11.  
In Figure 11, black represents bitumen, while white represents SBS. SBS in modified bitumen of the upper 1/3 was almost as much as the lower 1/3, which can be seen from Figure 11b,e. It shows that the stabilizer plays a good role in preventing SBS segregation. SBS was cross-linked, as shown in Figure 11c or Figure 11f, which was caused by the vulcanization reaction. The degree of vulcanization in SBS-modified bitumen was almost the same in the upper 1/3 and the lower 1/3. The same phenomenon occurred when using the stabilizer S:TMTD:ZnO:BHT:Al\({}_{2}\)O\({}_{3}\):2 SiO\({}_{2}\):2H\({}_{2}\)O = 60:16:4:20:1250.  
According to the phenomenon that the stabilizer developed based on the vulcanization reaction in this research can allow SBS to be cross-linked, it especially has the effect of preventing SBS segregation.