Elastic droplets rebound perfectly at high speed, opening new coating and material possibilities
Researchers discovered that polymer-based droplets can hit surfaces at high velocity and bounce back completely without splashing—a feat previously thought impossible. The finding could transform how companies apply coatings, design water-resistant materials, and manufacture products where precision and cleanliness matter.
Originaltitel: Balloon regime: Drop elasticity leads to complete rebound
When a highly elastic drop of a polymer solution hits a superhydrophobic surface at a high speed, a growing tail-like filament emerges vertically from the impact spot as the contact line recedes. Notably, the ligament transitions into a balloonlike shape before detaching completely from the surface (balloon regime). The ligament formation is attributed to liquid impalement upon impact into the surface protrusion spacing, and elastic forces due to polymers prevent ligament breakup. The detachment of the ligament happens when polymeric stresses balance or overcome the adhesion at the surface. This study shows that tuning droplet rheology and surface roughness enables droplets to rebound completely and without splashing at high impact speeds.