IN SITU ELECTRICAL RESISTIVITY CHANGES DURING BROMINE INTERCALATION IN CARBON FIBERS

摘要

In situ reaction kinetics of bromine intercalation in carbon fibers have been followed by measuring changes in their electrical resistivity during an intercalation and de-intercalation cycle. The study suggests that for well-graphitized P-55(HTT 3000 degrees C) and P-120 carbon fibers the reaction starts instantaneously and most of the charge transfer takes place within the first ten minutes with only 6% Br-2 weight uptake. It has also been shown that the threshold bromine vapor pressure lies below 26 Torr for P-120 fibers (T-pseudo similar to -15 degrees C) and 48 Torr for P-55 HT (T-pseudo similar to -5 degrees C) and is dependent on the structure of the host carbon fibers. The results have been compared with the earlier ex situ bromination studies on carbon fibers. Copyright (C) 1996 Elsevier Science Ltd [References: 16]