To clarify the effect and mechanism of hindered amine light stabilizer (HALS) on the UV aging behavior of asphalt binder, T622-HALS was selected as the modifier for UV aging resistance of asphalt. The physicochemical properties and microstructure of T622 light stabilizer were comprehensively analyzed. The light stabilizer-modified asphalt was prepared and placed in the UV radiation chamber for UV aging treatment. Scanning electron microscope and atomic force microscope were used to analyze the microscopic morphology evolution of light stabilizer-modified asphalt induced by UV radiation. The thermal properties and functional group composition changes in light stabilizer-modified asphalt during UV aging were studied by using the thermogravimetric and infrared spectroscopy combined testing system. The decay laws of the physical and rheological performances of light stabilizer-modified asphalt were studied during UV aging process, and the effect of light stabilizer on the UV aging behavior of asphalt binder was clarified. The research results indicated that HALSs could alleviate the microcracks and roughness change on the surface of asphalt and reduce the content of functional groups such as carbonyl and sulfoxide in asphalt. Furthermore, HALS could reduce the value difference of physical and rheological properties of asphalt before and after UV aging, significantly improving the UV aging resistance of asphalt binder.

中文翻译：

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光稳定剂改性沥青抗紫外老化性能的多尺度表征及机理

为明确受阻胺光稳定剂（HALS）对沥青结合料紫外老化行为的影响及机理，选择T622-HALS作为沥青抗紫外老化改性剂。对T622光稳定剂的理化性能和微观结构进行了综合分析。将光稳定剂改性沥青配制好，置于紫外辐射室中进行紫外老化处理。采用扫描电子显微镜和原子力显微镜分析了紫外辐射诱导的光稳定剂改性沥青的微观形貌演化。利用热重和红外光谱联合测试系统研究了光稳定剂改性沥青在紫外老化过程中的热性能和官能团组成的变化。研究了光稳定剂改性沥青在紫外老化过程中物理性能和流变性能的衰减规律，明确了光稳定剂对沥青胶结料紫外老化行为的影响。研究结果表明，HALSs可以缓解沥青表面的微裂纹和粗糙度变化，降低沥青中羰基、亚砜等官能团的含量。此外，HALS还可以减小沥青紫外老化前后物理和流变性能的数值差异，显着提高沥青结合料的抗紫外老化性能。