Dynamics of Semiflexible Colloidal Sheets in Shear Flow: Thermal Fluctuations

As 2D materials such as graphene, transition metal dichalcogenides, and 2D polymers become more prevalent, solution processing and colloidal-state properties are being exploited to create advanced and functional materials. Extending our previous work, we perform Brownian dynamics simulations of semiflexible colloidal sheets with hydrodynamic interactions and thermal fluctuations in shear flow. As a function of the ratio of bending rigidity to shear energy — a dimensionless quantity we denote S — and the ratio of bending rigidity to thermal energy, we observe behavior ranging from stochastic flipping to chaotic tumbling. The effects of these dynamical conformations on rheological properties such as viscosity and normal stress differences are quantified, and interesting non-monotonic dependence on S is observed.