目前,关于常温固化硅烷膜的研究报道较少,为进一步推广硅烷化处理的应用,采用硅烷偶联剂KH560(γ-缩水甘油醚氧丙基三甲氧基硅烷)作为成膜物有机成分,以正硅酸乙酯(TEOS)为成膜无机成分,通过添加乙酰基丙酮螯合剂和四乙烯五胺固化剂,获得有机/无机复合硅烷转化膜。用电导率测试仪检测溶液稳定性,用中华铅笔检测膜层硬度,用电化学方法研究复合硅烷膜在3.5%NaCl溶液中的耐蚀性。结果表明:最佳复合硅烷溶液主要成分用量(体积分数)为KH560 5%,TEOS 1%;最佳复合硅烷溶液在室温下可稳定12 h,添加固化剂四乙烯五胺常温55 min实现表干,固化剂最佳用量为2 mL(每100 mL复合硅烷溶液),固化96 h后膜层硬度达5H;最佳复合硅烷膜在3.5%NaCl溶液的自腐蚀电流密度下降至2.779×10-5A/cm2,腐蚀电位正移至-0.569 V,耐蚀性提高。
An organic-inorganic composite silane conversion film was obtained using silane coupling agent KH560( γ-glycidoxypropyltrimethoxysilane) as the organic part of the film forming material,tetraethylorthosilicate( TEOS) as the inorganic filming part,and tetraethylene pentamine as curing agent. The stability of the solution was measured by a conductivity meter,and the hardness of the coating was measured by a Chinese pencil. Moreover,and the corrosion resistance of the composite nanosilane film in a 3.5% sodium chloride solution was studied by an electrochemical method. Results showed that the optimal KH560 content in composite silane sol was 5%,and TEOS content was 1%.Furthermore,the composite silane sol was stable at room temperature for 12 hours,and surface drying was achieved after adding the curing agent tetraethylenepentamine at room temperature within 55 minutes. Meanwhile,the optimal content of curing agent was 2 mL,and the hardness of the coating reached 5H after curing for 96 h. In the 3.5% sodium chloride solution,the self-corrosion current density of the silane film decreased to 2.779×10-5A/cm2,and the corrosion potential positively shifted to -0.569 V,showing increased corrosion resistance.
Journal of Materials Protection
composite conversion coating