Kok, Baha VuralYalcin, ErkutOzdemir, Ahmet MunirOzdemir, Nisanur Gurcay2026-02-082026-02-0820251029-84361477-268Xhttps://doi.org/10.1080/10298436.2025.2553718https://hdl.handle.net/20.500.12885/5846This study aims to investigate the effects of the use of crumb rubber (CR) with polyurethane (PU) in bitumen modification on rheological and ageing properties. A novel modified palm-oil-based polyol was reacted with 4,40-diphenylmethane diisocyanate (MDI) to synthesise a polyurethane-derived polymer. Multiple stress creep recovery (MSCR), single point and frequency sweep tests were carried out. The analysis of the binders' viscoelastic behaviour was conducted using the Christensen-Anderson (CA) model. The complex viscosity was modelled using the Cross model. The low-temperature behaviour of the binders was determined by the bending beam rheometer (BBR) test, and the mixing-compaction temperatures were determined by the steady shear flow (SSF) method. Compared to single CR modification, the use of 4% PU in combination with 8% CR (8C + 4P) was found to broaden the relaxation spectrum, increase stiffness, improve shear-thinning resistance, and lead to a notable increase in resistance against ageing. Due to the polymeric networks developed in the 8C + 4P binder, it was determined that it exhibits superior elastic properties at high temperatures and also offers improved durability against low-temperature cracks. It was ascertained that the 8C + 4P binder demonstrated superior performance in both low- and high-temperature conditions compared to the 4% SBS modification, while there was no significant difference in terms of production temperatures.eninfo:eu-repo/semantics/closedAccessBitumenmodificationageingpolyurethanecrumb rubbermodellingArticle10.1080/10298436.2025.2553718261WOS:0015718933000012-s2.0-105016354784Q1Q1