Thermal history of carbon-fiber polymer-matrix composite, evaluated by electrical resistance measurement

The thermal history of carbon-fiber nylon-6 matrix composite was evaluated by measuring the electrical resistance in the fiber direction during heatin g, as the resistance was affected by the degree of crystallinity and the th ermal oxidative degradation. The resistance results were consistent with di fferent scanning calorimetry (DSC) and thermomechanical analysis (TMA) resu lts. The resistance measurement gave more information on the melting of the polymer-matrix than TMA. In particular, it distinguished more clearly betw een the melting of the reorganized crystalline phase and that of the origin al crystalline phase. The resistance measurement is more sensitive to the g lass transition of the polymer-matrix than DSC. (C) 2001 Elsevier Science B .V. All rights reserved.