Photothermal Self-Healing and Anti-Corrosion Coating Based on Phytic Acid-Doped Polyaniline
Phytic acid(PA)was used as a dopant for polyaniline(PANI)to prepare a series of phytic acid-doped polyaniline composites(PA/PANI)by varying the doping mass ratio of PA to PANI(m(PA)/m(PANI)).Then PA/PANI were employed to fabricate an intelligent anticorrosive coating with photothermal conversion capability for self-healing.The dispersion of PA/PANI in the coating was investigated,and the influence of m(PA)/m(PANI)and PA/PANI loading(w(PA/PANI))on the anticorrosive and self-healing properties of the coating was studied using scanning electron microscopy,electrochemical impedance spectroscopy,and neutral salt spray tests.Results demonstrate that the incorporation of PA/PANI significantly enhances the adhesion,anticorrosive performance,and self-healing capability of the coating,achieving a synergistic effect.When m(PA)/m(PANI)is 10 and w(PA/PANI)is 1%,the dispersion of PA/PANI in the coating is optimal,and the pull-off adhesion strength of the coating is increased from 2.06 MPa to 3.48 MPa.After immersion in a w=3.5%NaCl solution for 28 d,the low frequency impedance at 0.1 Hz(|Z|0.1 Hz)of the intact coating is two orders of magnitude higher than that of the pure resin coating,and no corrosion is observed during the 800 h salt spray test.Following just 10 s of near-infrared light irradiation,the scratches on the coating surface almost completely disappear,and its barrier properties are effectively restored.As a result,it can withstand a 400 h neutral salt spray test,with the|Z|0.1 Hz value increasing from 6.58×105 Ω·cm2 to 2.25×108 Ω·cm2.In contrast,the scratch width of the pure resin coating remains largely unchanged,being accompanied by obvious signs of corrosion.
NETL
NSTL
万方数据
