基于相对分子质量和热性质的改性沥青微观性能研究

Micro-properties of Modified Asphalt Based on Relative Molecular Mass and Thermal Properties

在90#基质沥青中加入一定比例的SBS,SBR,稳定剂和糠醛抽出油,分别制备成4种改性沥青并对其进行旋转薄膜烘箱试验和压力老化试验,得到短期老化和长期老化状态下的沥青样品.采用凝胶渗透色谱试验、差示扫描量热试验和热重试验,对改性沥青样品相对分子质量和热性质进行研究.结果表明:单掺SBR的改性沥青样品结构最不稳定,耐老化性能最差;稳定剂组和糠醛抽出油组改性沥青样品在老化过程中的大分子分解和小分子聚合得到了抑制,温度稳定性得到了提高;4种改性沥青样品在升温过程中质量损失主要分为小于200℃,200~420℃及420~550℃这3个阶段,其中第3个阶段反应最剧烈,质量损失速率最大.

A certain proportion of SBS,SBR,stabilizers and furfural extract oil was added in 90#base asphalt.After rolling thin film oven test and pressure aging test,the short-term aging and long-term aging asphalts were obtained.Changes of relative molecular mass and thermal properties of modified asphalts caused by temperature change were studied by gel permeation chromatography test,differential scanning calorimetry and thermogravimetric experiment.The results show that the structure of single-addition SBR modified asphalt is the most unstable,and its anti-aging property is the worst.Decomposition of macromolecules and polymerization of small molecules are suppressed during aging process of the stabilizer group and furfural extract oil group modified asphalt.Their temperature stability is improved.The mass loss of asphalt in the process of heating is mainly divided into three stages：less than 200℃,200-420℃ and 420-550℃.The reaction is strong in the third stage and the mass loss rate is the highest.