Matched-Pair MD Analysis of Functional-Group Effects in PVA-Inspired Cryoprotective Polymers

Poly(vinyl alcohol) (PVA) is a representative synthetic polymer for ice recrystallization inhibition (IRI), but the molecular origin of its activity is still not fully understood. In particular, the effects of functional-group chemistry, chain conformation, and interfacial contact are difficult to separate because they are strongly coupled at the ice–water interface.

In this study, we design a series of DP12 PVA-inspired model polymers with controlled variations in hydroxyl spacing, functional-group density, spacer structure, and hydrogen-bonding ability. Atomistic molecular dynamics simulations with TIP4P/Ice water are used to place pre-equilibrated polymer conformations near an ice–water interface. This setup allows us to compare how different functional groups and spatial arrangements influence local interfacial behavior.

Rather than evaluating IRI activity only by the number of ice-binding groups, we focus on molecular descriptors such as hydrogen-bond persistence, hydration-shell structure, polymer–ice contact, and recovery of ice-like water near the polymer. Through this matched-polymer approach, we aim to clarify how functional-group chemistry and interfacial geometry jointly regulate local ice growth. These results may provide molecular design principles for PVA-derived cryoprotective polymers.