冷冻干燥法制备有机蒙脱土及其改性沥青性能研究  

Study on Preparation of Organic Montmorillonite by Freeze-drying Method and Its Modified Asphalt Performance

作　　者：张帅 张健[1] ZHANG Shuai;ZHANG Jian(School of Automotive and Mechanical Engineering,Changsha University of Science and Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学汽车与机械工程学院

出　　处：《材料导报》2020年第4期37-42,共6页Materials Reports

基　　金：湖南省自然科学基金(2017JJ2263)~~

摘　　要：采用冷冻干燥法制备了有机化蒙脱土(OMMT),利用X射线衍射(XRD)仪和扫描电子显微镜(SEM)研究了冷冻干燥对OMMT层间距和表面形态的影响;使用OMMT制备了改性沥青,研究了它对改性沥青物理和高低温流变性能以及抗老化性能的影响。结果表明,冷冻干燥能够进一步扩大OMMT的层间距并细化OMMT颗粒的尺寸;OMMT的引入增加了改性沥青的软化点和车辙因子,显著提高了改性沥青的高温性能。对OMMT改性沥青进行薄膜烘箱老化(TFOT)和压力容器老化(PAV),分别模拟沥青的短期(ST)和长期(LT)老化。与原始沥青相比,OMMT改性沥青TFOT后的车辙因子和软化点变化较小,PAV后的蠕变刚度和疲劳因子较低,改性沥青的老化指数明显低于原始沥青。OMMT的引入增强了改性沥青的高温性能并有效抑制了改性沥青的热氧老化,当OMMT含量为3%(质量分数)时改性沥青具有最佳的性能。In this paper,organic montmorillonite(OMMT)was prepared by freeze-drying method.The effects of freeze-drying on the spacing and surface morphology of OMMT layer were studied by X-ray diffraction(XRD)and scanning electron microscopy(SEM).The modified asphalt was prepared by OMMT,and its influence on the physical and high-temperature rheological properties and anti-aging properties of the modified asphalt was studied.The results showed that freeze-drying could further increase the interlayer spacing of OMMT and refine the OMMT particle size.The introduction of OMMT increased the softening point and rutting factor of the modified asphalt,and significantly improved the high temperature performance of the modified asphalt.Film aging(TFOT)and pressure vessel aging(PAV)were performed to simulate short-term(ST)and long-term(LT)aging of asphalt,respectively.Compared with the original asphalt,the rutting factor and softening point of OMMT modified asphalt after TFOT changed little,the creep stiffness and fatigue factor after PAV were lower,and the aging index of modified asphalt was significantly lower than that of original asphalt.The introduction of OMMT enhances the high temperature performance of the modified asphalt and effectively inhibits the thermal oxygen aging of the modified asphalt,when the OMMT content is 3wt%the modified asphalt exhibits the best performance.

关 键 词：沥青 有机蒙脱土 冷冻干燥 流变性能 老化性能 

分 类 号：U414[交通运输工程—道路与铁道工程]