Molecular weight distribution of asphalt binders from Laser Desorption Mass Spectroscopy (LDMS) technique and its relationship to linear viscoelastic relaxation spectra
Molecular weight distribution of asphalt binders from Laser Desorption Mass Spectroscopy (LDMS) technique and its relationship to linear viscoelastic relaxation spectra
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DOI：
10.1016/j.fuel.2019.116444
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发表时间：
2020-02-15
期刊：
影响因子：
7.4
通讯作者：
Underwood, B. Shane
中科院分区：
文献类型：
--
作者：
Gundla, Akshay;Underwood, B. Shane
沥青粘合剂是一种复杂的粘弹性碳氢化合物，其性能取决于其物理和化学性质之间的相互作用，这两者对于成功理解材料同样重要。在这项研究工作中，利用激光解吸质谱 (LDMS) 技术建立了物理化学关系，将沥青粘合剂的分子结构与其粘弹性特性联系起来。从 LDMS 技术获得的分子量分布 (MWD) 数据用于建立沥青粘合剂的数均分子量和松弛谱宽度之间的关系，该沥青粘合剂是使用动态剪切流变仪通过线性粘弹性表征获得的。该关系表明，随着沥青结合料分子量的增加，它们需要更多的时间来松弛所产生的应力。此外，分子量分布的形状描述符表明，具有较大不对称性和峰度的沥青粘合剂需要更多时间来松弛所产生的应力。
Asphalt binder is a complex viscoelastic hydrocarbon, whose performance depends upon interaction between its physical and chemical properties, both of which are equally important to the successful understanding of the material. In this research effort, a physico-chemical relationship is developed by utilizing the technique of Laser Desorption Mass Spectroscopy (LDMS) to relate the molecular structure of asphalt binders to its viscoelastic properties. The molecular weight distribution (MWD) data obtained from the LDMS technique is used to develop a relationship between number average molecular weight and width of relaxation spectrum of asphalt binders obtained from linear viscoelastic characterization using dynamic shear rheometer. The relationship shows that as the molecular weight of asphalt binders increase, they require more time to relax the developed stresses. Also, the shape descriptors of the molecular weight distribution suggest that asphalt binders possessing greater asymmetry and kurtosis require more time to relax the developed stresses.