Polymer nano-foams for insulating applications prepared from CO2 foaming

International audienceAspects of the modeling of the thermal conductivity of polymer foams and a CO2 foaming process for the preparation of micro/nano-cellular polymer materials for insulating applications are reviewed. Generally speaking, the thermal conductivity of polymer foams is higher than that of air. However, it can be expected the Knudsen effect will give nano-cells the thermal insulation properties of aerogels. An analytical model of heat transfer in polymer foams may be used to predict the influence of the foam density and of the cell size on the thermal conductivity of polymer foams. This model derived from aerogel studies suggests the optimal foam density (0.1-0.2 g cm(-3)) and cell size (