当前位置: X-MOL 学术Int. J. Pavement Eng. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Improvements on the use of GPC to measure large-size microstructures in aged asphalt binders
International Journal of Pavement Engineering ( IF 3.8 ) Pub Date : 2020-12-01 , DOI: 10.1080/10298436.2020.1852561
Kecheng Zhao 1 , Yuhong Wang 1
Affiliation  

ABSTRACT

Gel permeation chromatography (GPC) is commonly used to study the aging and rejuvenation behaviours of asphalt binders, as the sizes of molecules and microstructures in asphalt binders change in such processes. The filtration procedure in preparing GPC specimens, however, may filter out some large-size microstructures in asphalt, making the measured molecular size distribution biased. To investigate this issue, two laboratory-aged asphalt binders and seven recovered ones were studied. Substances filtered from asphalt binders were analysed gravimetrically, followed by examinations using scanning electron microscope (SEM) and scanning transmission electron microscope (STEM). Relationships between binders’ rheological properties and the proportion of large molecular size (LMS) content based on the GPC chromatogram were investigated before and after counting the filtered substances. Results show that microstructures in the recovered asphalt binders differ from those in laboratory-aged ones in both size and morphology. While about 1% of laboratory-aged asphalt binders is obstructed by the GPC filter, 6–10% of recovered ones are blocked. Adding the filtered substances results in better correlations between the rheological properties and the proportion of LMS content. Therefore, in using GPC to analyze aged asphalt binders, it is recommended to count the filtered substances as part of LMS content.



中文翻译:

改进使用 GPC 测量老化沥青粘合剂中的大尺寸微观结构

摘要

凝胶渗透色谱法 (GPC) 通常用于研究沥青粘合剂的老化和再生行为,因为沥青粘合剂中的分子大小和微观结构会在这些过程中发生变化。然而,制备 GPC 试样的过滤过程可能会滤除沥青中的一些大尺寸微结构,从而使测量的分子尺寸分布出现偏差。为了研究这个问题,研究了两种实验室老化的沥青粘合剂和七种回收的沥青粘合剂。对从沥青粘合剂中过滤的物质进行重量分析,然后使用扫描电子显微镜 (SEM) 和扫描透射电子显微镜 (STEM) 进行检查。基于 GPC 色谱图,研究了过滤物质计数前后粘合剂的流变特性与大分子尺寸 (LMS) 含量比例之间的关系。结果表明,回收的沥青粘合剂的微观结构在尺寸和形态上都与实验室老化的不同。虽然大约 1% 的实验室老化沥青粘合剂被 GPC 过滤器阻塞,但 6-10% 的回收沥青粘合剂被阻塞。添加过滤后的物质会导致流变特性与 LMS 含量比例之间的相关性更好。因此,在使用 GPC 分析老化沥青结合料时,建议将过滤后的物质计入 LMS 含量。结果表明,回收的沥青粘合剂的微观结构在尺寸和形态上都与实验室老化的不同。虽然大约 1% 的实验室老化沥青粘合剂被 GPC 过滤器阻塞,但 6-10% 的回收沥青粘合剂被阻塞。添加过滤后的物质会导致流变特性与 LMS 含量比例之间的相关性更好。因此,在使用 GPC 分析老化沥青结合料时,建议将过滤后的物质计入 LMS 含量。结果表明,回收的沥青粘合剂的微观结构在尺寸和形态上都与实验室老化的不同。虽然大约 1% 的实验室老化沥青粘合剂被 GPC 过滤器阻塞,但 6-10% 的回收沥青粘合剂被阻塞。添加过滤后的物质会导致流变特性与 LMS 含量比例之间的相关性更好。因此,在使用 GPC 分析老化沥青结合料时,建议将过滤后的物质计入 LMS 含量。

更新日期:2020-12-01
down
wechat
bug