**9. Cross-Sectional Damage of Specimens after Tensile Test**

Figure 8 shows the cross-sectional morphologies of the tensile test pieces in the lowtemperature air environment and low-temperature water environment. The cross-sectional morphologies after 18 days and 90 days in low-temperature air environment are shown in Figure 8b,c, as there were more step-by-step undulations on the surface, and no additive particles. The cross-sectional morphologies changed little in the aging cycle, indicating that the environment has little effect on the adhesion of the rubber matrix. The crosssectional morphologies after 18 days, 54 days and 90 days in the low-temperature water environment are shown in Figure 8d–f, where a small number of additive particles appeared after 90 days, indicating that this environment can reduce the adhesion of the rubber matrix.

is far less than that in the low-temperature air environment.

Thus, this environment has an effect on the strength of the rubber waterstop, but the effect

**Figure 8.** Micromorphology of section.
