Improved thermal conductivity of polymeric composites fabricated by solvent-free processing for the enhanced dispersion of nanofillers and a theoretical approach for composites containing multiple heterogeneities and geometrized nanofillers

The thermal conductivities of Cyclic Butylene Terephthalate (CBT)-based composites containing nanofillers such as carbon nanotubes (CNTs) and carbon blacks (CBs) were experimentally and theoretically investigated. The recently developed composite manufacturing processing using solvent-free powder mixing and in-situ polymerization for the improved dispersion of nanofillers of various shapes and dimensions within a polymer matrix was applied to prepare nanocomposites. The experimentally measured the thermal conductivity of those composites, comparing the predicted values obtained from micromechanics models, taking into account the effect of both waviness of the nanofillers and multiple heterogeneities. The thermal conductivity of composites was profoundly affected by the waviness of CNTs. In addition, the interphase property between fillers and the polymer matrix was significant in determining the bulk thermal property of composites containing nanofillers.