Fabrication Of Functional Nanoiflm By Self-assembling And Electrodeposition Techniques And Film Characterization

Aluminum and its alloys have been widely used in many fields such as electronic,aerospace and biomedical industry, due to the light weight, easy modeling and recycling,excellent electric and thermal conductivity. However, their expanding application has beenlimited due to the poor corrosion resistance under severe conditions and for the alloyingthemselves. Thus, many researches have been carried out to investigate the well performedenvironmental friendly system for metal protection against corrosion. Triazinedithiols (TDTs)have been receiving increasing attentions recently for their high reactivity, well adhesive,lubrication, dielectric and superhydrophobic properties, also the functional polymericnanofilms of TDTs have strong combination with a variety of metal substrates and have beenwidely applied in different areas. It is expected that TDTs can replace the traditionalchromium inhibitions as a kind of novel environmental friendly system for metal protectionagainst corrosion.In the paper, we concentrated on the design and synthesis of6-(3-triethoxysilylpropyl)amino-1,3,5-triazine-2,4-dithiol monosodium salt (TES), and thefabrication of nanofilm on aluminum alloy surface. Based on the TES compound, differentsingle and composite functional polymeric nanofilms were prepared on aluminum alloysurface by combination of electrodeposition and self-assembling techniques, which could beapplied for corrosion protection of aluminum alloy under severe conditions for theirhydrophobic properties. The optimal potential for potentiostat polymerization wasinvestigated, and the formation mechanism of the TES polymeric nanofilm (PTES) wasstudied by cyclic voltammetry (CV). The properties of different single and compositenanofilms were also characterized.TES was synthesized by the reaction of cyanuric chloride,3-aminopropyltriethoxy silane(APTS) and NaSH, and the chemical structure of the compound was identified by FT-IR, MS,1H-NMR,13C-NMR. CV curves indicated that in the formation of the PTES, aluminumoxidation and the polymerization occurred simultaneously. The one-step potentiostat curvessuggested that the fabrication of PTES at high potentials would be much better than that at low potentials, also the current efficiency was high, and the optimal potential was7V in0.15M NaNO2aqueous solution with3mM TES. In the research, the performances ofdifferent single and composite nanofilms were also studied. The results showed that the thecomposite nanofilm of TES and hexadecyltrimethoxysilane (HDTMS) was the mosthomogenous, compact and had the highest coverage on aluminum alloy surface, which couldprotect aluminum alloy well against corrosion. It is expected that the technique can promotethe fabrication and application of TDTs and organosilane polymeric nanofilms.