Comparative Molecular Dynamics Study of Hydrogen-Bond Networks in Hydrogel and Glycolgel Systems

Hydrogel and glycolgel systems provide distinct solvent environments that strongly influence polymer network organization and intermolecular interactions. For polymer gels used under repeated deformation or mechanical stress, structural integrity is closely related to how polymer chains interact within the network.

In this study, molecular dynamics simulations were performed to compare the hydrogen-bonding behavior and structural organization of hydrogel and glycolgel systems. The comparison reveals a clear contrast between the two gels: glycolgel forms a more polymer-associated network, while water-swollen hydrogel retains a more solvent-expanded structure.

Hydrogen-bond fraction analysis showed that glycolgel has a higher contribution of polymer-polymer hydrogen bonds, indicating enhanced intermolecular association within the polymer matrix. In contrast, hydrogel showed relatively stronger polymer-water hydrogen bonding, consistent with greater solvent accessibility and a more dispersed polymer configuration. Radial distribution function analysis further supported the stronger short-range polymer correlations in glycolgel.

These findings demonstrate that solvent composition plays a key role in hydrogen-bond redistribution and network compactness in polymer gels. The stronger polymer association observed in glycolgel provides a molecular-level structural basis for understanding its experimentally observed tough behavior.