基于分子模拟的废大豆油再生沥青扩散行为  

Diffusion behavior of waste soybean oil rejuvenated bitumen based on molecular simulation

作　　者：史柯 马峰[1,2] 宋瑞萌 傅珍[3] SHI Ke;MA Feng;SONG Ruimeng;FU Zhen(Key Laboratory for Special Area Highway Engineering of Ministry of Education,Chang’an University,Xi’an 710064,Shaanxi,China;School of Highway,Chang’an University,Xi’an 710064,Shaanxi,China;School of Materials Science and Engineering,Chang’an University,Xi’an 710064,Shaanxi,China)

机构地区：[1]长安大学特殊地区公路工程教育部重点实验室,陕西西安710064 [2]长安大学公路学院,陕西西安710064 [3]长安大学材料科学与工程学院,陕西西安710064

出　　处：《化工进展》2024年第12期6794-6803,共10页Chemical Industry and Engineering Progress

基　　金：国家重点研发计划(2021YFB2601000)。

摘　　要：为了从分子尺度表征废大豆油再生沥青中各组分间的相互作用及其扩散行为,通过分子动力学模拟手段构建了基质沥青、老化沥青和再生沥青分子模型,并构建了双层沥青(沥青-沥青)模型,采用相互作用能与均方位移(MSD)表征了再生沥青模型中沥青组分的扩散行为以及废大豆油与沥青组分的结合强度,并评价了双层沥青模型的界面结合能及分子扩散行为。研究结果表明,废大豆油与沥青组分之间存在吸引作用,5%废大豆油再生沥青的相互作用能相较于2%废大豆油再生沥青提高约95.8%,表明随着废大豆油掺量的增加,相互作用能逐渐升高。通过计算MSD发现随着废大豆油掺量的增加,再生沥青模型中四组分的扩散能力逐渐增加,废大豆油能够有效改善老化沥青中四组分的分子迁移能力,但是组分迁移能力无法完全恢复至基质沥青水平。基质沥青-老化沥青模型的界面相互作用能相较于基质沥青-基质沥青下降约8.6%,表明分子尺度上新-旧沥青结合后其界面结合能力发生衰减,随着废大豆油掺量的增加,范德华相互作用逐步增强,基质沥青-8%废大豆油再生沥青的界面相互作用能与基质沥青-老化沥青基本一致。废大豆油掺量为2%~5%时,基质沥青-再生沥青模型中各组分有着较好的扩散速率。研究结果从分子尺度为废大豆油再生沥青的应用提供了理论依据。To gain insight into the interaction and diffusion behavior of components in waste soybean oil rejuvenated bitumen from a molecular scale,the molecular models of base bitumen,aged bitumen and rejuvenated bitumen were constructed by means of molecular dynamics simulation,and the double-layer bitumen(bitumen-bitumen)models were constructed.The interaction energy and mean square displacement(MSD)were utilized to characterize the diffusion behavior of components in the rejuvenated bitumen models and the binding strength between waste soybean oil and bitumen components.The interfacial interaction energy and molecular diffusion behavior of the double-layer bitumen models were evaluated.The results showed that there was an attractive interaction between the waste soybean oil and bitumen components,and the interaction energy of 5%waste soybean oil rejuvenated bitumen was approximately 95.8%higher than that of 2%waste soybean oil rejuvenated bitumen,indicating that with the increase of the amount of waste soybean oil,the interaction energy gradually increased.By calculating the MSD,it was found that with the increase of the amount of waste soybean oil,the diffusion performance of the bitumen components in the rejuvenated bitumen model gradually increased.The waste soybean oil could effectively improve the molecular migration ability of the bitumen components in the aged bitumen model,while the component migration ability could not fully be restored to the level of base bitumen.The interfacial interaction energy of the base bitumen-aged bitumen model decreased by approximately 8.6%compared with that of base bitumen-base bitumen model,showing that the interfacial interaction ability of the virgin-aged bitumen at the molecular scale was attenuated.With the increase of the amount of waste soybean oil,the van der Waals interaction was gradually enhanced,and the interfacial interaction energy of base bitumen 8%waste soybean oil rejuvenated bitumen was basically the same as that of base bitumen-aged bitumen.The components in the

关 键 词：再生沥青 废大豆油 分子动力学 均方位移 相互作用能 

分 类 号：U414[交通运输工程—道路与铁道工程]