The molecular architecture changes of crosslinked urethane during photo-oxidation was investigated by Fourier transform infrared spectroscopy (FTIR) in combination with two-dimensional (2D) correlation analysis. The 2D correlation FTIR spectroscopy provided insight into molecular architectural dynamics during photo-aging, where the sequential order of peak changes was determined upon perturbation with photo-aging. Photo-oxidation was monitored from the decrease in the peak intensity at 1537 cm⁻¹ (attributed to the urethane group) and the generation of the hydrogen bonded CO groups at 1698 cm⁻¹ immediately after urethane decomposition. Several notable peaks appeared (1712, 1650, and 1750 cm⁻¹) in the later stages, which were attributed to the free photo-oxidative product. In summary, photo-oxidation involved a cleavage of urethane crosslink and generation of end groups that formed hydrogen bonds with surrounding hydrogen bonding sites. Further degradation of the free photo-products was observed likely because of the small number of accessible hydrogen bonding sites due to the increasing heterogeneity of the internal structure.

通过傅立叶变换红外光谱（FTIR）结合二维（2D）相关分析，研究了光氧化过程中交联尿烷的分子结构变化。二维相关FTIR光谱学提供了对光老化过程中分子结构动力学的深入了解，其中峰变化的顺序是在受到光老化干扰后确定的。光氧化被从峰强度的降低在1537厘米监测^-1（归因于氨基甲酸乙酯基团）键合和C中的氢的生成ø组在1698厘米^-1氨基甲酸酯分解之后立即。出现几个值得注意的峰（1712、1650和1750 cm ^-1），这归因于游离的光氧化产物。总之，光氧化涉及氨基甲酸酯交联的裂解和端基的产生，所述端基与周围的氢键位形成氢键。观察到游离光产物的进一步降解可能是由于内部结构的异质性增加导致可及的氢键合位点数量少。