THERMAL TRANSPORT IN POLYSTYRENE AND POLYURETHANE FOAM INSULATIONS

The thermal transport in polystyrene (PS) and polyurethane (PU) foam insulations is described, with special emphasis on the radiative transfer. Calorimetric measurements of the total conductivity are performed in a guarded hot-plate device. The radiative properties of the foams are derived from infrared-optical investigations with an FTIR spectrometer. In the case of the PS foam, radiative properties are also extracted from calculations using the Mie scattering theory for infinite cylinders and platelets, representing the struts and walls of the foam cells, respectively. The total thermal conductivity of PU foams, including condensation effects of the blowing agent R 11, is modelled.