Electrical characteristics and pressure-sensitive response measurements of carboxyl MWNT/cement composites

In this study, electrical characteristics of pressure-sensitive carboxyl multi-walled carbon nanotube (MWNT)/cement composites with and without compressive loading were investigated. Experimental results indicate that the carboxyl MWNT/cement composites have both resistance and capacitance characteristics. Capacitance is insensitive to compressive loading, but the charging of the capacitor causes a linear increase in the measured resistance during DC measurement. The reversible pressure-sensitive responses of resistance to compressive loading can be extracted by removing the linear increase component. An AC measurement method can also be used to eliminate the effect of capacitor charging and discharging on the pressure-sensitive responses of carboxyl MWNT/cement composites. (C) 2012 Elsevier Ltd. All rights reserved.