(14c) Surface Functionalization of Different Plastic Substrates with a Hydrophilic/Oleophobic Perfluoropolyether Coating

Hydrophilic/oleophobic surfaces have been found in many applications including self-cleaning, anti-fogging, oil-water separation, etc. However, fabricating hydrophilic/oleophobic surfaces on plastic substrates is always challenging due to the low surface energy of plastic surfaces. In this work, various plastic substrates, i.e., acrylic, polystyrene, polyethylene, polytetrafluoroethylene, were functionalized with the combination of dip coating of perfluoropolyether (Zdol) and UV/ozone treatment. As a result, UV/ozone treatment could have different effects on those substrates coated with Zdol. Specifically, a post UV-ozone treatment is required for Zdol-coated acrylic or polyethylene to become hydrophilic/oleophobic, while the Zdol-coated polystyrene can have similar wetting behavior without the assistance of UV/ozone. The ATR FTIR spectrum indicated that the carboxylic group generated by UV/ozone treatment is the key for obtaining a low water contact angle. This strategy can be useful for the surface functionalization of plastics and have many applications in anti-fogging, anti-fouling and oil-water separation.