Nanocomposite hydrogels (NCHs) have emerged as promising materials for improving the mechanical integrity of traditional hydrogels, while offering biodegradability and regenerative capabilities. These properties make them attractive for applications such as inhibiting ice formation in Arctic soils. A key component of NCHs is polymer-grafted silica nanostructures, which influence water behavior at the nanoscale. This work employs coarse-grained molecular dynamics simulations to explore how variations in the polymer chain length and grafting density – defined as the number of grafted chains per unit surface area – influence the water-freezing behavior. Both the spherical nanoparticles and flat substrates are modeled as rigid silica surfaces functionalized with flexible hydrophilic polymers, while water is represented using the mW potential. The phase transitions through the spatial distribution of ice and liquid water, shifts in freezing temperature and changes in system dynamics are analyzed. Findings highlight that a critical range of grafting density significantly delays ice nucleation, offering design strategies for improving the freeze resistance and mechanical performance of NCH-based soil stabilizers.
