Acceleration of petroleum based mesophase pitch formation by PET (polyethylene terephthalate) additive

To improve mesophase formation in petroleum-based pitch, the PET (polyethylene terephthalate) additive reaction was studied. PFO (pyrolysis fuel oil) was used to prepare the petroleum pitch, and PET was added at a weight ratio of 0.33–1.50%. The chemical structure of PET-added pitch was analyzed by Fourier transform infrared spectroscopy, and the thermal properties were characterized by thermogravimetric analysis and the softening point method. Added PET provides oxygen during the pitch synthesis reaction, and the polycondensation of the pitch was accelerated by oxygen crosslinking. Thus, the softening point and carbonization value increased with the amount of PET added; moreover, the mesophase content increased by more than three times with 0.33 wt% PET addition. However, at more than 0.67 wt% PET addition, the fluidity rapidly decreased, so the mesophase spheres decreased in size and were independently distributed.