A low-cost method to produce superhydrophobic polymer surfaces

Here, we introduce a novel and inexpensive template-based structuring process to create superhydrophobic polymer surfaces adapted from the naturally occurring micro/nano structured surfaces found on the superhydrophobic leaves of the quaking aspen tree. Electroformed nanocrystalline nickel coupons were sandblasted and chemically etched to create a negative reproduction of the aspen leaf surface structure. These nanocrystalline nickel samples were then employed as re-useable templates and pressed against various polymers at elevated temperatures, transferring the desired superhydrophobic structure to their surfaces. This structuring process resulted in water contact angles above 150A degrees and tilt angles below 5A degrees for polyethylene, polypropylene and polytetrafluoroethylene samples. In addition, the effects of temperature, water drop size and surfactant concentration on these pressed polymer surfaces were investigated to assess potential application limitations for these surfaces.