抄録
This paper shows that the thermo-oxidative decomposition rate at elevated temperature measured by isothermal thermogravimetry (TG) is useful for evaluation of heat resistance of exfoliated graphite which is widely used as the material for gasket since asbestos has been banned. The decomposition onset temperature t_d obtained from TG operated in usual manner in which the sample is heated at a constant speed. t_d is the temperature that drastic decomposition is occurred so that it is inappropriate for estimation of heat resistance for prolonged use. TG instrument is also able to obtain v_d from measuring the decrease in weight at isothermal heating. The relationship between v_d and temperature is useful for estimating temperature effect for decomposition of graphite. Arrhenius plot provides the temperature effects on v_d. This kinetic approach is effective for estimating heat resistance of graphite gaskets.
