Abstract:Self-assembled nano-phase silane-based particle coating was prepared through sol-gel technique. Tetramethoxysilane and 3-glycidoxypropyltrimethoxysilane were used as precursors for the self-assembled sol-gel coatings. The silane colloidal particle size was analyzed by laser particle size measurement. The results indicate that the particle size is in nano-scale and the diameter of particles deceases with increasing dilution times. Gel permeation chromatography proves that the relative molecular mass of macromolecule in a referenced sol solution is 1 220−1 240 amu. A simulation model was proposed to study the siloxane structure. Fourier transform infrared spectra of solution and film prove the disappearing of epoxy bond. The results of solid-state ¹³C and ²⁹Si nuclear magnetic resonance experiments indicate the formation of Si—O—Si network. Potentiodynamic analysis shows that the self-assembled coating has excellent corrosion resistance. Salt fog tests prove that 2-methyl piperidine as inhibitor significantly improves the corrosion resistance of the self-assembled coating.

Key words: self-assembled coating; particle size; gel permeation chromatography; silane; corrosion resistance