Water Sorption in Epoxy–Amine Polymers with Aliphatic and Aromatic Hardener Moieties

Water sorption is known to induce detrimental effects in cured epoxy–amine polymers, significantly influencing their structural integrity and long-term performance. However, it remains unclear whether the nature of the hardener─aliphatic or aromatic─systematically affects the water sorption characteristics of the cured epoxy–amine network. In addition, the mechanistic pathways governing water absorption in these cured polymers have not yet been fully established. To address these questions, the present study combines detailed quantum-mechanical investigations with rigorous statistical analyses to elucidate both the influence of hardener chemistry on water sorption behavior and the underlying molecular mechanisms responsible for water uptake in cured epoxy–amine resins. The difference in the behavior of aliphatic and aromatic systems has been assessed by changes in conformational geometry during water adsorption.