利用紫外辐照强度为500 W/m²的紫外老化试验箱对添加不同含量复配光稳定剂的改性高密度聚乙烯（HDPE）复合材料进行大剂量紫外老化测试。通过傅里叶红外光谱（FTIR）测试发现，羰基指数与HDPE老化程度存在正相关，复配光稳定剂的添加显著降低HDPE的老化速度。通过旋转流变分析改性HDPE的分子量，发现随着复配光稳定剂添加量的增大，HDPE在老化初期的交联反应速度被抑制得越多。结合上述分析与力学测试结果发现，当改性HDPE材料需要承受200 kWh/m²的紫外辐照总量时，每100份基料中只需添加1.2份复配光稳定剂，改性HDPE材料就可以维持良好的性能，其断裂伸长率、拉伸强度和缺口冲击强度的保持率分别为57.7%、63.8%和105.0%。

The high-dose ultraviolet (UV) aging test of high density polyethylene (HDPE) composites modified by different contents of compound light stabilizer was tested by UV aging test chamber with UV irradiation intensity of 500 W/m². Fourier transform infrared spectroscopy (FTIR) test showed that the carbonyl index was positively correlated with the aging degree of HDPE. The aging rate of HDPE was significantly reduced by the addition of ultraviolet additives. The molecular weight of modified HDPE was analyzed by rotating rheology, which could found that the crosslinking reaction rate of HDPE was inhibited more with the increase of ultraviolet additives in the early aging period. Combined with the above analysis and mechanical test results, it was found that when the modified HDPE material needed to withstand the total ultraviolet irradiation of 200 kWh/m², the modified HDPE material could maintain good properties by only adding 1.2 phr compound light stabilizer in 100 phr matrix. The retention rates of elongation at break, tensile strength and notch impact strength were 57.7%, 63.8% and 105.0%, respectively.