改性SiO_(2)气凝胶聚氨酯复合涂层的制备及耐蚀性能研究  

Preparation and Anti-corrosion Properties of Silica Aerogelmodified Polyurethane Composite Coatings

作　　者：李丹鸿 杨腾逊 孙天翔 李兴霖冒 马程成 张玥[1] 陈守刚[1] LI Danhong;YANG Tengxun;SUN Tianxiang;LI Xinglinmao;MA Chengcheng;ZHANG Yue;CHEN Shougang(School of Materials Science and Engineering,Ocean University of China,Qingdao 266100,China)

机构地区：[1]中国海洋大学材料科学与工程学院,青岛266100

出　　处：《中国腐蚀与防护学报》2024年第1期167-174,共8页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金(52371081)。

摘　　要：通过提高SiO_(2)气凝胶的亲水性来提高水性聚氨酯(WPU)涂料的防腐性能。采用脲醛对SiO_(2)气凝胶进行改性,并通过Fourier红外光谱(FTIR)、扫描电子显微镜(SEM)等手段表征气凝胶的结构与微观形貌;通过电化学阻抗(EIS)、附着力实验和盐雾实验等研究了涂层的防腐性能。结果表明,添加亲水改性SiO_(2)气凝胶的涂层的附着力和腐蚀防护性能有明显提高,其中,添加1%亲水改性的SiO_(2)气凝胶涂层的附着力提升36%。在3.5%NaCl溶液中浸泡70d后涂层的低频阻抗模值超过6×10^(7)Ω·cm^(2),盐雾480 h后没有明显的鼓泡现象。Waterborne polyurethane(WPU)coating,a new kind of green material due to its excellent wear resistance,flexibility,low-temperature resistance and chemical medium resistance,has been widely attached attention to the field of marine corrosion protection.In this paper,hydrophilic modification of the hydrophobic silica(SiO_(2))aerogel was carried out by urea aldehyde modification.Then,the unmodifiedand modified-SiO2 aerogels as filler were added into the WPU coatings with doses 0.5%,1% and 2%,respectively,aiming to improve the anti-corrosion properties of WPU coatings.The functional groups and microstructure of SiO_(2) aerogel were characterized by Fourier transform infrared spectroscopy(FTIR)and scanning electron microscopy(SEM).These results proved that SiO_(2) aerogel was successfully modified by urea-formaldehyde.The anti-corrosion properties of coatings with different fillers were studied by contact angle test,electrochemical impedance spectroscopy(EIS),adhesion test and salt spray test.The results showed that the adhesion of the coating was significantly improved after adding hydrophilic-modified SiO_(2) aerogel.When 1%hydrophilic modified SiO_(2) aerogel was added,the adhesion of the composite coating was improved by 36%correspondingly,the low-frequency impedance modulus of the composite coating increased above 6×10^(7)Ω·cm^(2) after immersion in 3.5%NaCl solution for 70 d.There was no obvious bubbling phenomenon on the surface of the composite coating with 1%hydrophilic modified SiO_(2) aerogel after the 480 h salt spray testing,which showed its best anti-corrosion performance.Thus,it is concluded that the hydrophilic modification of the hydrophobic SiO_(2) aerogel by the urea aldehyde modification can improve the dispersibility of the hydrophobic SiO_(2) aerogel in the WPU coating,the interface compatibility with the coating and the barrier and shielding effect of the SiO_(2) aerogel on corrosive ions.Furthermore,the corrosion resistance of the WPU coating is improved.

关 键 词：SiO_(2)气凝胶 水性聚氨酯 亲水改性 腐蚀防护 长效防腐 

分 类 号：TG174[金属学及工艺—金属表面处理]