Analysis of the Effects of Hydrotalcite Inclusion on the Temperature-Sensing Properties of CNT-Epoxy Nanocomposites

Multiphase nanocomposites based on epoxy resin loaded with 1 wt% of multiwalled carbon nanotubes (MWCNTs) and different amounts of hydrotalcite clay (HT) are experimentally characterized in order to investigate their possible usage as temperature sensors and/or heating elements. In particular, the effects of clay content on the temperature dependence of the electrical and thermal properties of the samples are investigated. Moderate clay content (0.7% or 1% by weight) induces an improvement of the electrical and thermal conductivities, thus allowing to achieve fixed heating power levels with applied voltages lower than those required for MWCNT filled epoxy systems. The operating temperatures can be designed to be lower than that the glass transition reducing the risk of material degradation. Furthermore, the presence of clay increases the sensitivity compared to the (binary) MWCNT-based composites. The proposed multiphase nanocomposites could be used for the deicing of aircraft structural parts, in small boilers, floor pipes, and so on.