PVP修饰石墨烯/SBS复合改性沥青与混合料性能研究

Study on performance of PVP modified graphene composite SBS modified asphalt and mixture

针对传统石墨烯存在成本高、与基质沥青相容性和分散性差的问题,采用聚乙烯吡咯烷酮(PVP)对石墨烯(PVP-G)进行处理,基于针入度分级体系、PG分级体系与黏度分级体系指标评价了PVP修饰石墨烯复合苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)改性沥青混合料的常规针入度指标性能、流变特性、黏度特性,优化了适宜的PVP-G掺配比例,在此基础上,采用三大路用性能试验、浸水汉堡(APA)试验、半圆弯拉(SCB)疲劳试验与室内MMLS1/3试验,探讨了PVP-G/SBS复合改性沥青混合料的路用性能、疲劳性能与长期稳定性能。结果表明:添加PVP-G改善了SBS改性沥青的高温、低温和抗老化特性,增强了沥青胶结料的弹性恢复性能与抗变形性能,改善了低温抗断裂性能与应力释放性能。1.5%PVP-G/4.0%SBS复合改性沥青混合料有优异的高温抗永久变形性能、抗疲劳性能和抗水损害性能。在高温长期荷载及高温浸水综合作用下,1.5%PVP-G/4.0%SBS复合改性沥青混合料比5%SBS改性沥青混合料表现出了更优异的抗永久变形能力与耐久性。

In view of the high cost of traditional graphene,poor compatibility with matrix pitch and poor dispersion,polyvinylpyrrolidone is used to treat graphene(PVP-G),based on the index of penetration classification system,PG classification system and viscosity classification system.The conventional penetration index performance,rheological characteristics and viscosity characteristics of the PVP modified graphene composite SBS modified asphalt mixture were evaluated,and the appropriate PVP-G blending ratio was optimized.On this basis,three road performances were adopted tests,water immersion APA test,SCB bending tensile fatigue test and indoor MMLS1/3 test,discussed the road performance,fatigue performance and long-term stability of PVP-G/SBS composite modified asphalt mixture.the results shown that,the addition of PVP-G improved the high temperature,low temperature and anti-aging properties of SBS modified asphalt,enhanced the elastic recovery performance and anti-deformation performance of the asphalt binder,and improved the low-temperature fracture resistance and stress release performance.1.5%PVP-G/4.0%SBS composite modified asphalt mixture had excellent high temperature resistance to permanent deformation,fatigue resistance and water damage resistance.Under the combined effects of high temperature long-term load and high temperature water immersion,1.5%PVP-G/4.0%SBS composite modified asphalt mixture exhibited better resistance to permanent deformation and durability than 5%SBS modified asphalt mixture.