Hydrogen bonds dominated frictional stick-slip of cellulose nanocrystals

Crystalline cellulose, the most abundant natural polymer on earth, features exceptional physical and mechanical properties. Using atomistic simulation, this study reports behavior of cellulose-cellulose nanocrystal hydrophilic interface systematically examines impact loading direction, interfacial moisture, misalignment surface types. The density, orientation or distribution hydrogen bonds are shown to explain series findings presented here, including stick-slip behavior, stiffness recovery after an irreversible slip, direction-dependent weakening induced by hydration misalignment. Correlation analysis shows that, regardless various conditions, stress, shear velocity interaction energy strongly correlated with density bonds, which quantitatively supports central role bonding. Based correlation, friction force rendered a single bond is inferred be fHB ∼1.3 E-10 N under shearing speed 1 m s−1.