废旧塑料制备MPE颗粒对沥青改性的机理分析

Investigation into Performance and Modification Mechanism of Asphalt Modified by Polyethylene Made from Recycled Plastics

采用废旧塑料和增粘剂制备的MPE颗粒,可直接在道路沥青混合料拌和时直接投入,起到对道路沥青改性的作用,省去了在加工厂制备生产改性沥青的过程。为研究MPE对沥青的改性作用,选取两种70号基质沥青,测定其四组分含量,通过高速剪切设备制备不同MPE掺量的改性沥青,分别对其进行沥青性能的检测,绘制沥青性能随MPE掺量的变化曲线,同时应用奥特光学高倍显微镜对不同MPE掺量下的改性沥青微观形貌进行观测,并从流变学理论,应用KD方程分析MPE对沥青的改性机理。试验结果表明,MPE对沥青的高温、老化和水稳定性能具有明显的改善作用,同时MPE存在一个最佳掺量,约为沥青质量的6%。另外芳香分含量高的沥青有助于改性效果的提高。

Granular modified polyethylene made from recycled plastics and tackifier can be added to asphalt mix plant to modify asphalt,which avoids the process of modified asphalt production preparation in the factory.Two virgin asphalts,with their four constituents content tested,were chosen to study the MPE modified asphalt.Asphalts with different quantities of MPE were prepared by high speed shearing machine.Asphalt performance of every sample was tested,which varied with different MPE content,meanwhile,curves of performance versus MPE content were drawn.Besides,Microstructure of modified asphalt with different MPE content was observed by high power microscope.To analyze modifying mechanism of MPE,Kriege Dougherty Equation in rheology theory was cited.At last,all the test results and analysis indicated that MPE can obviously improve asphalt performances such as high temperature performance,aging resistance and water stability. However,there is an optimal MPE content which is 6%of asphalt mass and more aromatic hydrocarbon in asphalt is benefit for the modification.