Carbonization behavior of coal tar pitch modified with benzoquinone

A soluble fraction of coal tar pitch (CP) in tetrahydrofuran (THF) was reac ted with p-benzoquinone (BQ) at 160 and 180 degrees C and followed by carbo nization and graphitization. The reaction and carbonization behavior were m onitored in-situ by using differential scanning calorimeter, high-temperatu re H-1 NMR and high-temperature ESR. The reactions of CP and BQ resulted in an increase in molecular weight with an increase in BQ concentration. Such molecular weight increases led to the formation of a less ordered structur e due to the reduced mobility of the molecules. The relative order of the c arbonized materials was determined by using polarized light microscope and X-ray diffraction. The molecular size of the precursor was recognized as an important factor in determining the morphology of carbon materials. (C) 20 00 Kluwer Academic Publishers.