The microstructure and surface characteristics of fluorine‐based copolymer coatings deposited by the static breath method

Abstract

We constructed a coating with controllable microstructure on the substrate by static breath figure (BF) method. In the atmosphere of water, when the fluorine‐containing 1H,1H,2H,2H‐perfluorooctyl polyacrylate‐block‐polystyrene copolymer (PTFOA‐b‐PS (4 h)) synthesized via atom transfer radical polymerization for 4 h was dissolved in carbon disulfide (CS2) and then coated on the silicon wafer, the concentrated pore size and uniform micro‐pore structure was successfully constructed on the surface. However, the hydrophobicity of the resulting microporous coating was not so good. An interesting result is that when the copolymer solution of PTFOA‐b‐PS (2 h) in tetrahydrofuran (THF) was used under the MeOH/H2O atmosphere (the methanol content was 60% or 80%), the microsphere coating can be produced on the substrate surface to obtain the excellent hydrophobicity. The water contact angles (WCAs) were 148.8 ± 1.8° and 150.3 ± 1.8°, respectively. Energy dispersive X‐ray spectrometer (EDS) results showed that the fluorine element was enriched in the outerfield of the microsphere coating. The low surface energy of fluorine combined with the rough and complex structure of the microspheres can effectively improve the hydrophobicity of the coating.