Enhancement corrosion resistance of (3–glycidoxylpropyl)- silsesquioxane hybrid films and its validation by gas-molecule diffusion coefficients using MD simulation
Based on silsesquioxanes (SSO) derived from hydrolytic condensation of (g–glycidoxylpropyl) trimethoxysilane (GPMS) and tetraethoxysilane (TEOS), two hybrid films, f-GPMS-TEOS-SSO (f-GTS) modified with 10 wt-％ TEOS and f-GTS modified with 50 wt-％ DGEBA (f-GTSD), were prepared. The anticorrosion properties (corrosion potential, Ecorr, and corrosion current density, Icorr) of the bare aluminum alloy (AA) and the two films on AA were tested by electrochemical measurements with typical potentiodynamic polarization curves. The Icorr values of three samples were significantly different with the order of f-GTSD<f-GTS<AA， which implies that the DGEBA addition in the f-GTSD coating indeed enhances the electrochemical corrosion resistance. Two different 3D-amorphous cubic unit cells, cell(f-GTS) and cell(f-GTSD), as models were employed to investigate self-diffusion coefficients by MD simulation for the NO2, SO2 and H2O molecules. All the three self-diffusion coefficients of NO2, SO2 and H2O diffusing in cell(f-GTSD) were less than the coefficients in cell(f-GTS), which validates the corresponding anticorrosion-experiment results. Two reasons that the addition of DGEBA in the system of f-GTS lead to the decrease of the gas self-diffusion coefficient compared to the f-GTS system were discussed.
Silsesquioxanes (SSO) Coatings Anticorrosion Molecule dynamics simulation Mean-square displacement Diffusion coefficient
Gang XIE Peng WANG Lijiang HU
Full School of Chemical Engineering and Materials, Heilongjiang University, Harbin 150080 China Full Department of Environment engineering, Harbin Institute of Technology,Box 713, Harbin 150001, C
国际会议
重庆
英文
190-197
2008-06-09（万方平台首次上网日期，不代表论文的发表时间）