Akademik Veri Yönetim Sistemi
The 40th International Conference of Polymer Processing Society (PPS-40), Auckland, Yeni Zelanda, 22 - 25 Nisan 2025, cilt.4, sa.16246, ss.271, (Özet Bildiri)
SBS is used to modify bitumen due to its excellent durability, resistance to permanent deformation, and enhanced flexibility. The conditions used to blend SBS with bitumen are critical in determining the morphology, thermal and rheological properties of these blends, particularly concerning ageing. The effects of varying shear rate and mixing time on SBS-modified bitumen were examined to assess their impact on ageing and material performance. Higher shear rates and prolonged mixing significantly increase bitumen oxidation, changing functional groups, signalling oxidative ageing. SBS modification enhanced thermal stability by altering the degradation mechanism increasing the onset temperature of thermal degradation. The specific heat capacity (Cp) and glass transition temperature (Tg) of the blends also increased with longer mixing times and higher shear rates, largely due to ageing [1]. Rheological analysis showed increased shear rates and extended mixing times resulted in higher complex shear modulus (G*) and phase angle (δ) values, correlating with improved rutting resistance and higher Performance Grade (PG) temperatures. This suggests greater resistance to deformation at elevated temperatures, improving long-term durability [2]. Examination of blend morphology revealed mixing significantly influenced SBS dispersion. Prolonged mixing and higher shear rates promoted blend homogeneity, although ageing led to phase separation, particularly the asphaltene component. The swelling behaviour of the SBS phase contributed to its stable dispersion within the bitumen, confirmed from optical, confocal laser scanning (CLSM) and atomic force (AFM) microscopy [3,4].