Effect of Thermal Aging on Polyurethane Degradation and the Influence of Unsaturations in the Hard Segment Academic Article in Scopus uri icon

abstract

  • This research focuses on synthesizing two types of polyurethanes (PUs): one with saturated C¿C bonds (SPU) and another with unsaturated CC bonds (UPU), primarily in the hard segment. Both types of PUs underwent thermal aging for 30 days at 150°C in an air atmosphere to investigate the influence of unsaturation on their thermal degradation. The samples, both before and after aging, were characterized using FT-IR, XRD, TGA, DSC, mechanical testing, and SEM. Additionally, the percentage of weight loss was measured. Similar changes were observed in both SPU and UPU after thermal aging. Thermal degradation resulted in mass losses of approximately 5% for SPU and 10% for UPU, accompanied by chemical alterations in the PUs, as evidenced by FT-IR. Mechanical testing revealed a decline in performance for both materials, with notable reductions in yield strength and elongation at break. UPU exhibited a more pronounced degradation in mechanical properties compared to SPU. SEM analysis further confirmed surface degradation in both materials. Among the two PUs, UPU demonstrated higher susceptibility to thermal degradation. This study provides valuable insights into how the unsaturation in diols or polyols used in PU synthesis influences thermal degradation and the resulting changes in material properties. The findings also highlight the potential performance implications for SPU and UPU when exposed to temperatures exceeding their processing or operational limits. © 2025 Wiley Periodicals LLC.

publication date

  • January 1, 2025