摘要
用γ-(2,3-环氧丙氧)丙基三甲氧基硅烷(GPTMS)对纳米二氧化硅(SiO_2)表面进行修饰,再引入苯胺合成了化学键合的核壳型聚苯胺(PANI)接枝SiO_2(SiO_2@PANI)溶胶;经乙烯基三甲氧基硅烷(VTMS)原位包埋后得到可直接涂在镁锂合金(Mg-Li)表面的SiO_2@PANI/VTMS水性溶胶。使用红外光谱(FT-IR)、X射线粉末衍射(XRD)、X射线光电子能谱(XPS)、透射电子显微镜(TEM)等手段表征了SiO_2@PANI粒子的结构与形貌;测量极化曲线和电化学阻抗(EIS)表征了SiO_2@PANI/VTMS涂层对Mg-Li合金的防腐蚀性能;讨论了苯胺用量和VTMS用量对SiO_2@PANI的粒径、涂层疏水性以及防腐蚀性能的影响,给出了可能的防腐蚀机理。结果表明,m(An):m(TEOS)=7:100、m(VTMS):m(TEOS)=4:4的SiO_2@PANI/VTMS涂层对Mg-Li合金具有优异的防腐蚀性能,涂层水接触角高达145.5°,电化学阻抗值达到7.5×104Ω·cm^2,腐蚀电流密度仅为4.47×10-8A/cm2。
Nano-SiO_2 was firstly modified by（3-glycidoxypropyl）-trimethoxylsilane（GPTMS）, and then was grafted with polyaniline（PANI） to form nano-SiO_2（SiO_2@PANI） sol with core-shell structure through chemical bonding. Further, the nano-SiO_2（SiO_2@PANI） sol was in situ embedded with vinyl trimethoxysilane（VTMS） to prepare the water-born SiO_2@PANI/VTMS sol, which can be used as coating material for Mg-Li alloy. The structure and morphology of SiO_2@PANI were characterized by Fourier transform infrared spectrum（FT-IR）, X-ray diffractometer（XRD）, X-ray photoelectron spectroscopy（XPS） and transmission electron microscopy（TEM） etc. The corrosion resistance of the coating was assessed by potentiodynamic polarization curves and electrochemical impedance spectra（EIS）. The effect of anilineand VTMS-dosage on the particle size, hydrophobic property and corrosion resistance of SiO_2@PANI were also examined, and the possible anticorrosion mechanism was proposed. The results show that the SiO_2@PANI/VTMS coatings have a high hydrophobic angle, which could reach 145.5° when m（An）：m（TEOS）=7：100 and m（VTMS）：m（TEOS）=4：4. The composite coatings on Mg-Li alloy present excellent corrosion resistance performance with electrochemical impedance value 7.5 × 104Ω·cm2 and corrosion current density 4.47×10-8 A/cm^2.
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2018年第1期42-50,共9页
Chinese Journal of Materials Research
基金
国家自然科学基金(51401113)
黑龙江省博士后科研启动金(LBH-Q13171)~~
关键词
材料失效与保护
聚苯胺
纳米SIO2
化学键合
镁锂合金
防腐蚀
materials failure and protection, polyaniline, nano-silica, chemical bonding, Mg-Li alloy,anticorrosion
