Mesophase pitch prepared from aromatic hydrocarbons with the use of HF/BF₃

New methods are described for the catalytic and thermal preparation of mesophase pitches from naphthalene and anthracene with the use of HF/BF₃. Detailed analysis of FT-IR, FD-Mass, ¹H-NMR, and ¹³C-NMR spectra of the pitches indicate a high level of naphthenic hydrogen which assists oxidation during stabilization. The naphthalene mesophase pitches possessed good spinning properties to produce carbon fibres 8-12 μm in diameter, with a tensile strength σ_T = 2.5 GPa and a tensile modulus E_T = 280 GPa, increasing to σ_T = 3.5 GPa and E_T = 800 GPa after graphitization. The ease with which properties such as fluidity, solubility, and softening-point temperature can be controlled and the use of recyclable catalysts enable the production of high-quality carbon fibres at resonable cost.