| It is a new, economical and environmental protecting surface-treatment technology to apply silane coumpling agents to mental pretreatment, which can obviously improve the adhesion between organic coatings and metallic substrate, and the anti-corrosion of coatings. Conventional chromating and phosphating, which are dangerous to the health of human being and environments in industrial application, can be replaced by silane coupling agents surface treating to attain the aim of anti-corrosion.Imide ring were introduced to the backbone of the novel silanes molecules through modifyingγ-Aminopropyl triethoxysilane (γ-APS) by anhydride or dianhydnde with appropriate molecular structutre. Because of strong polarity of imide ring, Si-OH functional group on thus obtained modified silane coupling agents has stronger acidity, and so the metal-siloxane (Me-O-Si) or siloxane (Si-O-Si) covalent bonds are more stable, more difficult to hydrolyze. The polarity of imide ring can enhance the silane's adhesion to the surface of metal. The hydrophobic macromolecular moiety (imide ring, benzene ring) increase the density of silane film, and thus enhance anti-corrosion ability of the film.In this thesis, thermal imidization and chemical imidization were employed to complete the synthesis of novel silanes coupling agents bearing imide structure. Their thermal stability was studied by TGA, and it was found that the weight loss percentages of novel silanes were very low before 300℃.The application of novel SCA bearing imide structure to treating metals (copper, steel) was probed, and systematic study of application condition, including fabrication of treating liquid and their storage stability, and their anti-corrosion effect were investigated. The relationship between molecular structure of novel SCAs and treating effect was preliminarily established. It is revealed that novel SCAs with characteristic bis-silicon structure modified by bulky anhydride and dianhydride possess the desired anti-corrosion effect.
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