Impact of CO₂ chemisorption on dynamics of polyamines across multiple time scales

Polyamines are promising materials for carbon dioxide (CO₂) capture due to their ability to form carbamates in dry conditions and bicarbonates in humid environments at room temperature. While the mechanisms of amine–CO₂ interactions and overall CO₂ uptake capacity have been widely studied, the impact of CO₂ sorption on the dynamics of polyamines remains underexplored. This gap limits the rational design and optimization of polyamine-based sorbents for high-performance CO₂ capture. Our previous work demonstrated that CO₂ sorption significantly alters the segmental dynamics of both bulk polyamines and supported polyamine films, as observed by broadband dielectric spectroscopy (BDS) and differential scanning calorimetry (DSC) [1]. In this study, we systematically investigate the influence of CO₂ chemisorption on polyamine dynamics using a comprehensive suite of techniques, including BDS, nuclear magnetic resonance (NMR) spectroscopy, rheology, and DSC. Our results reveal a dramatic, previously unreported effect of CO₂ uptake on the dynamic behavior of bulk polyamines across a wide range of time scales—from secondary relaxations to terminal flow. These findings offer new insight into structure–property relationships in polyamine sorbents and provide a foundation for the rational design of next-generation materials for CO₂ capture. Details of the experimental observations and their implications for material design will be presented in the poster.