Self-assembly in drying complex fluid at low capillary number

摘要

We study the pattern formation induced by drying colloidal suspensions and polymer solutions in a vertical Hele-Shaw cell immersed in a reservoir. The contact line speed is controlled by pumping out the solution from the reservoir. At low capillary number stick-slip motion of the receding contact line can be observed for silica suspensions. Periodic strips spontaneously form during drying. We study the strip periodicity and deposit morphology as a function of the receding velocity and pH of the solution. In the same conditions, dried polymer films are almost flat.