二氧化硅基有机-无机防腐蚀杂化膜的制备及性能

传统的钢铁表面覆膜技术如磷化、铬酸盐钝化等污染严重,硅烷化和有机-无机杂化涂层用于金属预处理则具有耐温、耐腐蚀等优点,又利于环保.以正硅酸乙酯、γ-氨丙基三乙氧基硅烷为原料,采用溶胶.凝胶法制备了SiO2基有机-无机杂化材料.通过红外光谱对不同温度处理的杂化材料进行了分析,以差示扫描量热法研究了杂化材料在不同温度下的吸放热反应,结合对杂化溶胶涂覆于钢铁基体表面形成涂层的塔菲尔曲线分析,对杂化膜的保护性能进行了研究.结果表明:涂层试样在N2气氛下300℃热处理,可以保证涂层中Si-O-Si键等最大程度地键合,并有效保留了有机组分,从而有利于保证杂化材料涂层的完整性,较大地提高了基体钢铁的耐腐蚀性能,可作为金属表面涂装处理工序中良好的中间过渡层.

Preparation and Properties of Silica-Based Organic-Inorganic Hybrid Anticorrosion Coatings

Silica - based organic-inorganic hybrid material was prepared from tetraethoxysi-lane (TEOS) and γ-aminopropyhriethoxy silane by sol-gel meth-od. The chemical bending feature and endothermic- exothermic reaction of the hybrid materials hoat-treated at different tempera-tures were investigated by means of infrared spectrometry and dif-ferential scanning calorimetry (DSC). Electrochemical analysis (Tafel curve) was oarried out to evaluate the corrosion protection action of the sprayed hybrid coating for the steel substrate. Re-sults indicate that after being heated at 300 ℃ in nitrogen, opti-mized Si - O - Si bending was realized in the hybrid coating, and the organic ingredients were effectively retained in the coating. Subsequently, the hybrid coating had good integrality and was a-ble to effectively increase the corrosion resistance of the steel sub-strate. In one word, the hybrid coating might be used as an inter-mediate coating for surface finishing of metals.