Thermal conducting properties of aligned carbon nanotubes and their polymer composites

Carbon nanotubes (CNTs) with well aligned, highly regular structures possess advanced properties like high crystalline orientation and low thermal interface resistance. These properties enable them to become effective thermal interface materials (TIMs) in thermal management. However, the application is constrained by their fragility in the external environment. Additionally, air gaps and defects make aligned CNTs a poor thermally conducting model. Therefore, aligned CNT/polymer composites have been widely developed to acquire the combination of high thermal conductivity and other excellent properties. There are still some challenges which require further studies on improving the CNT quality, enhancing the interfacial strength and reducing the interface thermal resistance. This paper reviews recent progress in the thermal conduction of CNTs and their polymer composites. The synthesis methods are discussed along with the thermal conducting property dependence on the aligned CNT structure and morphology as well as the interface properties in details.