Preparation and pyrolysis behavior of modified coal tar pitch as C/C composites matrix precursor

Abstract

Medium-temperature coal tar pitch (CPT) which is used as C/C composites matrix precursor is modified by phenolic resin (PF) in the presence of p-toluene sulfuric (PTS) acid as catalyst. Fourier transform Infrared (FT-IR) spectroscopy techniques, polarized-light microscopy and thermaogravimetric analysis (TGA) are employed to study on structure and thermal behavior of the modified CPT, respectively. Results show that the high molecular weight aromatic species in modified CPT is found and also confirmed by the results from FT-IR and TGA analysis. Otherwise, coking yield of modified CTP has improved by 13% and soft point decreased by 25°C compared with raw CPT. Moreover, the modification contributes to an improvement in the optical textures of resultant matrix precursor materials of C/C composites.