Dynamic wetting of non-newtonian fluids: multicomponent molecular-kinetic approach

Hydrodynamic models are generally applied to describe the dynamic wetting of newtonian or non-newtonian fluids on a solid surface. Conversely, the molecular-kinetic paradigm is only utilized for spreading newtonian fluids while considering the movement of a contact line as a molecular hopping process. This study extended the molecular-kinetic paradigm to the wetting behavior of non-newtonian fluids, while assuming there are n fluid components at the contact line regime interacting simultaneously with a solid surface during front movement. The limiting cases of the derived model at slow and fast moving speeds were discussed. Moreover, the derived model was validated based on dynamic contact angle data of three carboxymethylcellulose (CMC) aqueous solutions measured using the force-balance method. Best-fit parameters were used to interpret the wetting dynamics of CMC solutions.