The thermal conductivity of rigid closed-cellpolyurethane (PU) foams under long-term aging has been studied.Similarity in the kinetics of changes in the physical and mechanicalcharacteristics of PU foams under progressive aging is established,which is attributed to the effect of matrix destruction. It is foundthat rigid foams have cell walls of various strength whose impacton the kinetics of changes in the physical characteristics of thefoams under long-term aging is ascertained. The results ofpredicting the thermal conductivity of PU foams by the method oftemperature-time analogy and establishing the limits of itsapplication are discussed. The research presented is of interest bothfor the determination of foam durability and in terms of theecological aspect when replacing freons by alternative foaming agents.
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