Nanocomposite hydrogels have recently gained attention as soil amendments to improve soil strength, but their large water content makes them prone to freezing in cold, Arctic environments. A typical solution involves the incorporation of hydrophilic monomers, or nanofillers as crosslinking agents, to create hydrogels with nanoscale domains that prevent water from freezing. We plan to perform coarse-grained molecular dynamics simulations to investigate the mechanical behavior of nanocomposite hydrogels, and their effects on the freezing behavior of water. These simulations will contain fully- and partially-flexible polymer chains and explicit water molecules following the mW potential. Firstly, our goal is to perform rheological experiments under steady shear to calculate viscosity, and elucidate the gel’s shear-thinning properties. These changes can be attributed to the hydrogel’s internal network topology, specifically increased crosslinking density and formation of percolated structures that reinforce the 3D network. Secondly, we will also analyze the composition and distribution of ice and liquid water within the hydrogels’ interstitial pores, and also measure changes in freezing temperatures. We believe our findings will provide insight into the structure-property relationships governing hydrogel mechanics, as well as demonstrate whether antifreeze properties arise from confinement effects or through the nature of polymer-water/nanofiller pairwise interactions.
