Preparation and Characterization of Mesophase Pitch via Co-Carbonization of Waste Polyethylene/Petroleum Pitch

The low-cost petroleum pitch and waste polyethylene (WPE) were used as raw materials to prepare the mesophase pitch by co-carbonization method and the forming mechanization of mesophase pitch was also investigated. Polarized microscopy, softening point, Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) were used to characterize and analyze the properties and structure of the mesophase pitch. The results showed that the carbonization yield of the modified pitch was high when 1-2 wt% WPE was added and the property of mesophase pitch (MP1-450-4 and MP2-450-4) prepared by thermal polymerization was excellent. Moreover, when the treatment temperature was above 420 °C, the mesophase development of the modified pitch may be entire and 100% streamline texture mesophase can form. During the co-carbonization of WPE/petroleum pitch, a large number of naphthenic structures and methylene bridges may be generated, which can improve the properties of the obtained mesophase pitch.