Brominated pitch-based carbon fibers

Pitch - based carbon fibers, brominated during 2-144 hrs, have been characterised by their electrical resistivity in the temperature range 10-300 K, micro-Raman spectroscopy in the spectral region 100-3100 cm(-1) and thermogravimetric analysis (TGA) with the purpose of determination of bromine state and changes in the fiber structure on molecular level in these materials upon the bromination process. The obtained data have been explained by degradation of graphite network, increasing of finite crystalline phase, appearance and increasing of carbon in amorphous state, and the gain of graphite layers number adjacent to bromine. Some suggestions concerning bromine state in carbon fibers have been done.