Polyamide 6 Conformation and Swelling Transitions in Formic Acid, Dichloromethane, Chloroform, 1,2‐Dichloroethane, and Water Using All Atom Molecular Dynamics Simulations

This paper reports the dissolution and inter and intra‐molecular structural properties of Polyamide 6 (PA6) in formic acid (FA), dichloromethane (DCM), chloroform, 1,2‐dichloroethane (1,2‐DCE), and water. The backbone torsional angle probability shows a significant gauche state in water, chloroform, and 1,2‐DCE, indicating poor solvent behavior. In contrast, FA and DCM exhibit efficient solvation behavior. Spatial distribution functions (SDF) showed stronger H‐bonding interactions between PA6—water and PA6—FA systems. In contrast, in DCM, 1,2‐DCE, and chloroform systems, solvent molecules were uniformly distributed near the methylene (CH 2 ) group in PA6, indicating weak van der Waals interactions. The PA6 show chain show swelling in FA and water via strong inter‐connected hydrogen bonded network, while it adapts rigid rod like conformation in the DCM, 1,2‐DCE, and Chloroform. Overall, these results will help to determine the roles of polar and apolar solvents in accelerating the dissolution of PA6 at room temperature.