Polymer-Based Nano-Composites for Thermal Insulation

The growing need for efficient energy use prompts for effective thermally insulating materials. Nano-composites represent an important class of materials able to fulfill these needs, enabling both sizeable energy savings and specific applications where thermal insulation has to be coupled to mechanical robustness and lightness, like in automotive and aerospace applications. In view of these developments, this review summarizes the topic of polymer-based nano-composites for thermal insulation. The theme is introduced overviewing the features of the matrix-filler interfaces and of the available models of thermal conductivity, with a mention of the most used types of polymeric matrices. The main three different types of polymer-based nano-composites for thermal insulation, that is, polymeric nano-foams, syntactic foams and all-solid nano-composites, are then reviewed. For each class of material, the thermal insulation performance of selected examples is highlighted, with explicit reference to the material's structure and constitutional peculiarities (like type or size of the filler, specific filler surface functionalizations, etc). A resuming table reporting the thermal insulation performance of selected composites is also included in the review. Finally, an outlook on the possible developments in the field is given.