Electrical resistance and microstructure of latex modified carbon fiber reinforced cement composites

Abstract

The electrical resistance, flexural strength, and microstructure of carbon fiber reinforced cement composites (CFRC) were improved greatly by adding water-redispersible latex powder. The electrical resistance of CFRC was investigated by two-probe method. The input range of CFRC based strain sensors was therefore increased, whereas electrical resistance was increased and remained in the perfect range of CFRC sensors. The analysis of scanning electron microscopy indicated that elastic latex bridges and a latex layer existed among the interspaces of the adjacent cement hydration products which were responsible for the enhancement of the flexural strength and electrical resistance. The formation mechanism of the elastic latex bridges was also discussed in detail. The continuous moving of two opposite interfaces of the latex solution-air along the interspaces of the adjacent hydrated crystals or colloids was attributed to the formation of the elastic latex bridges.

Keywords

carbon fibers / composites / cement / latex / electrical properties / flexural strength

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