Surface treatment of polymer microfibrillar structures for improved surface wettability and adhesion

The effects of altering the polymer surface characteristics on adhesion qualities of bio-inspired fibrillar adhesives were found to be significant. Treatment of fibril tip surfaces in polymer fibrillar adhesives improved their wettability and adhesion capacity. Surface modifications of fibril tips involved UV/Ozone and oxygen plasma treatments for making the fibril tips more hydrophilic. These surface treatment effects, however, tend to degrade over time (rendering hydrophobic recovery). The stability of treated (hydrophilic) surfaces was improved, while retaining their wettability, through coating with a polyelectrolyte such as polyethyleneimine (PEI) via self-assembly.