MAKING FUNCTIONAL SURFACES WITH ACRYLIC PLATES

By using sandpaper of different grit, we have polished smooth plates of acrylic to cover their surfaces with disordered but near parallel micro-grooves. This procedure allowed us to transform the acrylic surface in a functional surface; by using the capillary rise of silicone oil up to an average height h, we found that h evolves as a power law of the form h~tⁿ, where t is the elapsed time from the start of the capillary flow and n is close to 0.5, for different inclinations of the plate and different grit. Such a behavior is in agreement with the theoretical predictions for the capillary rise in very tight capillary wedges.