氧化石墨烯因其片层间存在的范德华力和氢键作用，具有易成膜的优点，通过过滤或者旋涂过程，很容易在基底上形成氧化石墨烯薄膜。目前，氧化石墨烯薄膜在分离领域被广泛研究，并显示出了良好的分离性能(Huang H,Mao Y,Ying Y,et al.Salt concentration,pH and pressure controlled separation of small molecules through lamellar graphene oxide membranes[J]. Chemical Communications,2013,49(53):5963-5965.)。虽然氧化石墨烯薄膜在干燥的条件下具有良好的机械性能和稳定性，但当其处于潮湿或者水环境中时，氧化石墨烯薄膜的机械性能会变得不稳定，氧化石墨烯粒子易从薄膜上脱落下来，造成薄膜的破裂。聚乙烯亚胺(PEI) 是一种超支化聚合物，由于PEI上存在伯胺、仲胺和叔胺等官能团，所以PEI能够和氧化石墨烯纳米粒子通过胺基和羧基发生静电相互作用。
Dye wastewater is one of the main harmful industrial wastewater, which mainly comes from dye and dye intermediate production industry. It is composed of mother liquor crystallized by various products and their intermediates, materials lost in the production process and sewage washing the ground. With the development of dye industry, its wastewater has become the main source of water pollution. Therefore, how to remove dye molecules from wastewater is always the focus and research focus.
Membrane separation technology has been widely used in dye industry because of its advantages of high efficiency, low energy consumption, easy operation and low investment. Membrane separation is a process based on the separation of materials, which USES the physical and chemical properties of each component in the mixture to realize the separation of substances. Therefore, membrane materials are the basis of membrane separation technology.
Due to the van der Waals force and hydrogen bonding between the layers, go has the advantages of easy film formation. It is easy to form go films on the substrate through filtration or spinning process. At present, go films are widely studied in the field of separation, Also, good separation performance was demonstrated (Huang H,Mao Y,Ying Y,et al.Salt concentration,pH and pressure controlled separation of small molecules through lamellar graphene oxide membranes[J]. Chemical Communications, 2013,49 (53) : 5963-5965.). Although go film has good mechanical properties and stability under dry conditions, when it is exposed to moisture or water, the mechanical properties of go film will become unstable. Go particles are easy to fall off the film, causing the film to break. Polyethylene imine (PEI) is a hyperbranched polymer. Due to the presence of primary amine, secondary amine, tertiary amine and other functional groups on PEI, the electrostatic interaction between PEI and go nanoparticles can occur through the amine and carboxyl groups.