Impact of solar exposure on chemical and rheological properties of hybrid polymer modified bitumen with recycled plastics

This study examines the effects of summer solar exposure in Casablanca, Morocco, on the chemical and rheological properties of virgin bitumen and hybrid Polymer-Modified Bitumen (PMB) incorporating Recycled Low-Density Polyethylene (R LDPE) and Recycled Polypropylene (R PP) with Styrene-Butadiene-Styrene (SBS) copolymer, with and without Sulphur. Hybrid PMB formulations were prepared by adding 4% SBS and other additives to base bitumen. Ultraviolet (UV) aging, rheological tests, Differential Scanning Calorimetry (DSC), and Fourier Transform Infrared Spectroscopy (FTIR) were conducted to analyze aging mechanisms and performance. Results demonstrate that hybrid PMB modified with R LDPE and R PP shows superior aging resistance compared to SBS-PMB, while the addition of Sulphur further enhances durability. These findings highlight the potential of recycled polymers and Sulphur in improving bitumen performance under solar exposure.