Oleophobic/Adhesive Janus Self-Standing Films Modified with Bifurcated Short Fluorocarbon Chains as Transparent Oil Stain-Free Coating with Attachability

Oil stains negatively affect the performances of our belongings and industrial equipment. However, conventional oleophobic coatings contain complex nanostructures or long fluoroalkyl chains, which are environmentally unsafe and limit their applications. In addition, the integration of film transparency, flexibility, and oleophobicity represent extremely challenging tasks. Herein, we report self-standing oleophobic/adhesive Janus membranes with flexibility and transparency, which were composed of environmentally low impact materials: poly(vinyl alcohol) (PVA)/SiO₂ nanoparticle composites modified with bifurcated short fluorocarbon chains via the sol-gel method. The optimized coating performed the oleophobicity (oleic acid sliding angle = 27.9°) and reduced more than 50% of oil adhesion on glass substrate. It also maintained its transparency (93.13% at wavelength of 550 nm) after the exposure to oil mist. Moreover, the coatings were able to attach to various substrates to provide them an oleophobicity. Our results demonstrate the important role to develop oleophobic coating materials with low environmental impact.