Electrical resistivity of sheet-type rubber composite heaters with carbon nanomaterials as filler

Abstract

Sheet-type heaters were prepared using FKM rubber (fluoroelastomers composed of vinylidene fluoride and other fluoroalkenes) as a matrix with carbon black, multi-walled carbon nanotubes and cup-stacked carbon nanotubes as fillers. The electrical resistivity, thermal expansion, PTC (positive temperature coefficient) effects and filler dispersion properties were evaluated. The results showed that the nanocarbons were dispersed homogeneously and that the temperature dependence of the electrical resistivity could be controlled by the addition of nanocarbon fillers. The optimum PTC effects were observed for the samples with cup-stacked carbon nanotubes heat-treated at 1500°C.