How to Make Plastic Surfaces Simultaneously Hydrophilic/Oleophobic?

Hydrophilic/oleophobic surfaces are desirable in manyapplicationsincluding self-cleaning, antifogging, oil-water separation,etc. However, making plastic surfaces hydrophilic/oleophobic is challengingdue to the intrinsic hydrophobicity/oleophilicity of plastics. Here,we report a simple and effective method of making plastics hydrophilic/oleophobic.Plastics, including poly (methyl methacrylate) (PMMA), polystyrene(PS), and polycarbonate (PC), have been coated with a perfluoropolyether(PFPE) (i.e., commercially known as Zdol) via dip coating and thenirradiated with UV/Ozone. The contact angle measurements indicatethat the treated plastics have a lower water contact angle (WCA) andhigher hexadecane contact angle (HCA), i.e., they are simultaneouslyhydrophilic/oleophobic. The Fourier transform infrared (FTIR) resultssuggest that UV/Ozone treatment introduces oxygen-containing polargroups on the plastic surfaces, which renders the plastic surfaceshydrophilic. Meanwhile, more orderly packed PFPE Zdol molecules, whichis due to the UV-induced bonding between PFPE Zdol and the plasticsurface, result in the oleophobicity. Moreover, the simultaneous hydrophilicity/oleophobicityof functionalized plastics does not degrade in aging tests, and theyhave superior antifogging performance and detergent-free cleaningcapability. This simple method developed here potentially can be appliedto other plastics and has important implications in the functionalizationof plastic surfaces.

Automated summary

Researchers have developed a simple and effective method to make plastic surfaces hydrophilic/oleophobic by coating them with a perfluoropolyether and irradiating them with UV/Ozone. The treated plastics exhibit both hydrophilicity and oleophobicity, as confirmed by contact angle measurements and FTIR results. These functionalized plastics show superior antifogging performance and detergent-free cleaning capability, and do not degrade in aging tests.