Expansion Of The Graphite Surface Modification Of Composite Applications

In this paper, the surface of expanded graphite(EG) was modified by chemical oxidation method, and then functionalized expanded graphite oxides was prepared by treatment of expanded graphite oxides(EGO) with epoxy prepolymer.The effect of EGO and functionalized EGO on the thermal properties,the crystallization behavior and the interfacial compatibility of polyamide-6(PA6) was studied, respectively.EGO was obtained by oxidating EG with different chemical oxidation methods. EGO with the higher degree of oxidation(h-EGO) was obtainded based on Hummers'methods. The structure of EGO was characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, thermogravimetry analysis (TGA) and X-ray diffraction (XRD) analysis. Furthermore the dispersion behavior of EGO in different organic solvents and electrical conductivity were investigated. The results show that the degree of oxidation is closely relevant to the dosage of oxygenate but irrelevant to extension of reaction time, and the volume resistance of h-EGO is 105 times higher than that of EGO and 106 times than that of EG.EGO-AGE and EGO-EGDE were prepared by the surface chemical grafted reaction of EGO with Allyl Glycidyl Ether(AGE) and Ethylene Glycol Diglycidyl Ether(EGDE) respectively,which was proved by FTIR, TGA, XRD and Raman spectroscopy. Their dispersion behavior in water was investigated through ultraviolet spectrophotometer (UV) and digital camera. The water exfloation of EGO-AGE and EGO-EGDE was limited due to the reduction of oxidized functional groups.The scanning electron microscope (SEM) images indicate that EGO and EGO-EGDE can completely exfoliated and uniformly distributed within polyamide-6 matrix, which means that the interfacial compatibility between them and polyamide-6 matrix increases. XRD, TGA, differential scanning calorimetry (DSC) were used to study the thermal properties and the crystallization behavior of the EGO/PA6 and EGO-EGDE/PA6 composites. It was found that the addition amount of EGO and EGO-EGDE has an effect on the thermal properties and the crystallization behavior.