| Metal materials are the most widely used in marine equipment.Once corrosion occurs,it will lead to serious damage and huge economic losses.Superhydrophobic surfaces represent a significant technological breakthrough in recent studies over corrosion protection of metals.This paper was based on methacryl fluoropropylPOSS?F-POSS?,which was introduced into acrylate polymer by solution free radical polymerization.Using the product fluorinated POSS acrylate copolymers as film-forming materials,coatings were prepared on Q235 steel by breath figure method.The wetting property,corrosion resistance and stability stability of the coatings were also studied.The main research results are as follows:?1?Hepta?3,3,3-trifluoropropyl?-tricycloheptasiloxane trisodium silanolate(Na3O12Si7?C3H4F3?7)was synthesized through hydrolysis condensation and methacryl fluoropropylPOSS?F-POSS?was synthesized through corner-capping reaction.The F-POSS was introduced into acrylate polymer by solution free radical polymerization to synthesize fluorinated POSS acrylate copolymers.FTIR,1H NMR,29Si NMR,GPC and TGA were used to characterize the products.The results showed that F-POSS and fluorinated POSS acrylate copolymers with different F-POSS content were successfully synthesized.The molecular weight distribution of the copolymers was 1.8-2.0,the glass transition temperature was 22-47?and the initial decomposition temperature was199.3-242.8?.?2?Using fluorinated POSS acrylate copolymers as film-forming materials,honeycomb porous surfaces were successfully prepared on Q235 steel by breath figure method.The surface morphology,element content,roughness and wettability of the coatings were measured by SEM,EDS,AFM and contact angle measurement.The effects of F-POSS content and copolymer concentration on the surface morphology and wettability of the coatings were studied systematically,and the acid-alkali resistance,thermal stability and durability of the as-prepared superhydrophobic coating were also studied.The results showed that when the content of F-POSS was 25%and the concentration of copolymer was 30 mg/mL,the surface of the Q235 steel coating had micro-nanostructure,the roughness was 228 nm,the content of fluorine element was up to 26.59%,the water contact angle reached 153°,and the coating had superhydrophobic property.Meanwhile,the superhydrophobic coating of fluorinated POSS acrylate copolymer showed good chemical stability and thermal stability.?3?In neutral 3.5wt%NaCl solution,the corrosion protection abilities of different coatings were studied by electrochemical impedance spectroscopy and Tafel polarization curves,and the longterm corrosion protection effects of different coatings were investigated deeply by monitoring the changes of the electrochemical impedance spectroscopy for a long time.The electrochemical measurements showed,in neutral3.5wt%NaCl solution,the superhydrophobic coating of fluorinated POSS acrylate copolymer has the best anti-corrosive effect.The|Z|0.01Hz was more than 108?cm2,which was 5 orders of magnitude higher than that of the substrate,and remained above105?cm2 after 20 days of immersion.Meanwhile,corrosion current density icorr was the lowest,at 2.01×10-99 A cm-2,the inhibition efficiency?IE%?was up to 99.98%.In addition,the anti-corrosive properties of different coatings in acidic and alkaline 3.5wt%NaCl solution were studied.The results showed that the anti-corrosive effects of the superhydrophobic coating were also the best.The|Z|0.01Hz were more than 108?cm2,and remained above 105?cm2 after 20 days of immersion,icorr were the lowest,and IE%were 99.96%and 99.95%,respectively.The as-prepared superhydrophobic coating of fluorinated POSS acrylate copolymer not only had good sustainable anti-corrosion property under neutral condition,but also under acidic and alkaline conditions. |
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