Thermal Conductivity of Carbon Nanofibre-Polypropylene Composite Foams

Carbon nanofibre-reinforced polypropylene nanocomposites containing from 5 to 20 wt.% of carbon nanofibres and a chemical blowing agent were melt-compounded and later foamed using compression-moulding. Alongside their foaming behaviour analysis and cellular characterization, foams showing an increasingly finer isometric cellular structure with increasing the amount of nanofibres, their thermal conductivity was determined using the Transient Plane Source Method (TPS). Contrarily to the electrical conductivity, which has previously been shown to rise with increasing the amount of carbon nanofibres [1], the addition of the nanofibres did not significantly alter the thermal conductivity of the PP foams, their value being mainly affected by the relative density, only slight differences being assessed for the higher expansion ratio PP-CNF foams.