Super hydrophobic surfaces with contact angles (CA) >150o and sliding angles (SA) <10o have been the subject of numerous basic and applied studies due to their potential use in "easy cleaning" applications and as ice-phobic(reduction of ice adhesion) coatings for a variety of surfaces. Consequently, the effects of nano - and micro - roughness as well as the chemical composition of various surface coatings were studied, with the objective to shade light on the suitability of surface super-hydrophobicity to reduce ice adhesion. Results indicated that selected roughness and surface chemistry reduced ice adhesion by a factor of 18 compared to untreated surfaces.Since the surface structuring lasted only a small number icing/de-adhesion cycles, a comprehensive study has been undertaken to enhance the durability in aggressive environments. Two routes have been proposed. In the first approach, the roughness has been designed by replication of nano and micro structures by thermoplastic polymers (in collaboration with UMass Lowell, USA).Thus, templates containing nano-micro particles bonded to various substrates have been developed to serve as the base for further replication by roll to roll technique. In the second one, the roughness used is based on nano and micro particles with covalent bonding to the substrates by radiation chemistry (in collaboration with Bar Ilan University, Israel). Hence,a novel system, comprisingUltra Violet (UV) reactive silica nanoparticles (NPs)based on the photo sensitive benzophenone(BP) was studied. Experimental results indicated that the resulting covalent bond formation by UV radiation chemistry is very effective in obtaining strong bonding between the silica NPs and the polymer comprising the nanocompositecoating. The adhesion strength between the silica and the polymer was evaluated by applying shear stresses using an AFM tip. It has been concluded that the proposed replication and radiation chemistry provide an effective route for the preparation of superhydrophobic nanocomposite with reduced ice adhesion and improved durability for long service times.
