A Synthesis on the Effects of Two Commercial Recycled Plastics on the Properties of Bitumen and Asphalt

The desire to develop sustainable infrastructure, including pavement structures and materials, is ever increasing in recent times. One opportunity is to partially replace high-cost bituminous binder with low-cost recycled plastic in asphalt mixtures. This synthesis combines the various research efforts to understand the effects of two commercially available recycled plastics, known as MR6 and MR10, on bituminous binders and asphalt mixtures. Using common test methods from the United Kingdom, the United States and Australia, generally consistent and significant effects were observed in various base bitumen grades and various common asphalt mixture types. Binder resistance to flow and binder elasticity both increased significantly and were associated with the three to four grade increases under the Performing Grading system. Similarly, mixture stiffness and mixture resistance to deformation increased significantly, while crack resistance and moisture damage resistance were not significantly affected. The effects of MR6 and MR10 were generally similar to the effects associated with conventional polymer modification of asphalt binders and asphalt mixtures, particularly those effects associated with plastomeric polymers.