The 6-mercapto-1,3,5-triazine-2,4-dithiol monosodium(TTN) compound was used to fabricate an organic film on pure copper. The polymer plating process of TTN on pure copper in Na2CO3 aqueous solution and the growth mechanism of poly(6-mercapto-1,3,5-triazine-2,4-dithiol)(PTT) film were studied by means of cyclic voltammetry. The polymer plating under galvanostatic mode at 0.05 mA/cm2 was conducted to generate PTT film on pure copper in the same electrolyte with different polymer-plating time. The film mass was determined by electronic balance and the insoluble fraction in tetrahydrofuran(THF) Is tested. The performance of organic film formed on copper surface was investigated preliminarily by potentiodynamic polarization and electrochemical impedance spectroscopy(EIS). It is found that a slight peak measured at 0 V vs SCE attributes to the oxidation of copper and generated Cu+ or/and Cu2+ to produce Cu-TTN complex,then a strong oxide peak is observed at 0.311 V vs SCE due to the polymerization of TTN for the increase of the film thickness. Electrochemical measurement results reveal that 10 min is an optimum polymer-plated time to obtain high quality film. The results of potentiodynamic polarization show that current density decreases from 1.85 μA/cm2 for bare copper to 0.168 μA/cm2 for polymer-plated copper while polymer-plated time is 10 min. The charge transfer resistances of bare copper and polymer-plated copper are 937 Ω·cm2 and 11.12 kΩ·cm2,respectively. The film capacitor for polymer-plated copper is as low as 1.82 μF·cm2. The EIS results confirm the results of potentiodynamic polarization and reveal that a homogenous and compact film is obtained by polymer plating technique.
Polymeric nano-film on the surface of Mg-Mn-Ce magnesium alloy was fabricated by polymer plating of 6-dihexylamino-1,3,5-triazine-2,4-dithiol monosodium(DHN) to improve its corrosion resistance.The electrochemical reaction process was analyzed by cyclic voltammetry and two obvious peaks of oxidation reaction were observed.The static contact angle of distilled water on polymer-plated surface can be up to 106.3°while on the blank surface it is 45.8°.Potentiodynamic polarization results show that the polymeric film can increase the corrosion potential from -1.594 V vs SCE for blank to -0.382 V vs SCE.The results of electrochemical impedance spectroscopy indicate that the charge transfer resistances of blank and polymer-plated Mg-Mn-Ce alloy are 485Ω·cm^2 and 2 717Ω·cm^2,respectively.The method of polymer plating can provide a novel approach for fabricating hydrophobic film on Mg-Mn-Ce alloy surface and improving its anti-corrosion property.
