废胶粉/再生低密度聚乙烯复合改性沥青研究

Research on Modified Asphalt by Waste Tire Rubber Powder and Reclaimed Low Density Polyethylene Composite

依据正交试验原理,以废轮胎橡胶粉(WTR)和再生低密度聚乙烯(RPE)为改性剂,采用高速剪切法制备了不同工艺条件(剪切温度、剪切时间、剪切速率)下的WTR/RPE复合改性沥青.以针入度、软化点、延度为评价依据,确定了WTR/RPE复合改性沥青的最佳工艺,并进一步对WTR/RPE复合改性沥青的性能进行了评价.结果表明:最优的工艺参数为剪切温度180℃,剪切时间90min,剪切速率5 000r/min;复合改性沥青的针入度减小,软化点和黏度增大.WTR和RPE的建议掺量(均以沥青质量计)分别不宜超过15%和4%.

According to the principle of orthogonal test, modified asphalt by waste tire rubber powder （WTR） and reclaimed low density polyethylene（RPE） was prepared by high-speed shear mixing method in different processing conditions （shear temperature, shear time and shear rate）. Penetration, softening point and ductility were used as the basis for evaluation to identify the optimal processing condition to pro- duce WTR/RPE modified asphalts and then evaluate the WTR/RPE modified asphalts＇ performance. The test results show that the optimal processing parameters are. shear temperature of 180 ℃, shear rate of 5 000 r/min and shear time of 90 rain. After adding WTR and RPE, the penetration is reduced, while softening point and viscosity of modified asphalt are increased. The recommended content of WTR and RPE should be less than 15% and 4%（by mass）, respectively.