疏水改性氧化石墨烯/环氧复合涂料的制备及其防腐性能研究

以叔碳酸缩水甘油酯(E-10P)为疏水单体,通过环氧与羧酸的共价键合,在氧化石墨烯(GO)表面引入疏水性支化碳链,改性后的氧化石墨烯(F-GO)作为防锈填料加入环氧树脂中得到F-GO/环氧复合涂料。通过红外光谱、拉曼光谱、X-射线衍射、热重分析对F-GO的结构进行表征,通过场发射扫描电镜观察F-GO及复合涂料的微观形貌,并通过电化学阻抗、极化曲线和盐雾试验测试了复合涂料的防腐性能。结果表明:E-10P可利用其空间效应阻碍片层的团聚;疏水效应可提高F-GO的热稳定性和与环氧树脂的相容性;与空白环氧涂层相比,当复合涂料中F-GO质量分数为0.2%时,厚度为20~25 μm的防腐涂层的腐蚀电流可由2.358 6×10 ^-6 A/cm ²下降至2.000 2×10 ^-11 A/cm ²,阻抗值可由1.1×10 ⁷ Ω·cm ² 提升至6.9×10 ⁹ Ω·cm ²。

Preparation and Anticorrosion Property of Hydrophobic Modified Graphene Oxide/Epoxy Composites

A highly branched hydrophobic carbon chain is introduced on the surface of graphene oxide(GO) by the covalent bonding of epoxy and carboxylic acid, wherein, glycidyl ester (CarduraTM E-10P) is used as a hydrophobic monomer. The modified graphene oxide(F-GO) is added as an anti-rust filler to epoxy resin to obtain the F-GO/epoxy composite material. Structural properties are characterized by Fourier transform infrared spectrometer (FT-IR), Raman spectroscopy, X-ray diffraction (XRD) and Thermal gravimetric (TG). In addition, morphological properties are observed with Field-emission scanning electron microscopy (FE-SEM). The corrosion behaviors of the coated steel substrates are evaluated by Neutral salt spray (NSS) and Electrochemical measurements. The results show that E-10P can inhibit the agglomeration of lamellae by its steric effect. The hydrophobic effect enhances the thermal stability of F-GO and compatibility of epoxy resin. When the additive amount of the composite is 0.2%, the corrosion current of anti-corrosive coating with a thickness of 20-25 μm can be reduced from 2.358 6×10 ^-6 A/cm ² to 2.000 2×10 ^-11 A/cm ² and the impedance value can be increased from 1.1×10 ⁷ Ω·cm ² to 6.9×10 ⁹ Ω·cm ².