**3. Experimental setup**

Because of the very slow degradation of polymer materials under natural conditions, therefore researchers from various countries have developed various artificial accelerated aging test methods to study the aging mechanism of polymer materials. The fluorescent ultraviolet lamp aging test has a high acceleration rate, and the aging resistance of the material can be obtained in a short time. It is one of the most commonly used artificially accelerated aging test methods for polymer materials.

**Figure 2.** *a. a schematic diagram of the square pyramid test bench. b. the pyramid skylight structures.*

In this study, we verify the effect of UV accelerated aging on pyrolysis through comparative experiments.
