Increasing the Strength of Polycrystalline Freshwater Ice by Introducing Cellulose Nanoparticles into Its Structure

It is shown that when the content of cellulose nanoparticles in polycrystalline freshwater ice increases from 0 to 1 wt % its compressive strength almost doubles. The concentration dependence of the compressive strength of ice composites reaches saturation at about 1 wt %. It is found that an increase in the concentration of cellulose nanoparticles leads to a transition from brittle to ductile fracture of the ice composites, as well as an increase in both the relative strain corresponding to the peak stress and the specific work required to achieve the peak stress. An increase in the concentration of nanoparticles introduced into ice to 1 wt %, which are additional crystallization centers, leads to an almost fourfold decrease in the average size of its grains. The predominant factor determining the strength of pure ice and ice composites is the size of the intergranular cracks formed, which is proportional to the average size of the ice grains.