SBS改性沥青机理研究进展

Progress in Mechanism of SBS-modified Asphalts

介绍了沥青的特性、苯乙烯-丁二烯-苯乙烯三嵌段共聚物(SBS)的性能,分析了SBS与基质沥青之间的溶胀性和相容性问题,着重论述了SBS改性沥青机理的研究进展,指出机理主要分为物理共混和化学改性两类:物理共混——SBS微粒受到沥青组分中油分的作用发生溶胀而均匀分散在沥青中,SBS与沥青之间没有发生化学作用,只是一种分子间作用力;化学改性——加入添加剂使沥青和SBS之间发生加成、交联或接枝等化学反应,形成较强的共价键或离子键,改善沥青的化学性质。提出化学改性是提高SBS改性沥青路用性能的重要手段。

The characteristics of asphalt and styrene-butadiene-styrene tri-block copolymer （SBS） were introduced. The swelling and compatibility properties between SBS and asphalt were analyzed. The advances in mechanism of SBS-modified asphalts were reviewed emphatically. It was pointed out that modified mechanism can be divided into physical mixing modification and chemical modification. Physical mixing means that the SBS particulates absorb the oil fractions from the asphalt to swell up and disperse evenly throughout the asphalt without chemical reaction between SBS and asphalt. Chemical modification means that crosslink or graft reactions happen between SBS and asphalt by adding additives to improve the chemical properties of asphalt. Furthermore, chemical modification is the important method to improve the properties of SBS-modified asphalt.