||Aging of polyurethane insulation foamed with second- and third-generation blowing agents.
Wilkes, K. E. ;
Gabbard, W. A. ;
Weaver, F. J. ;
||USDOE Assistant Secretary for Energy Efficiency and Renewable Energy, Washington, DC (United States). ;Environmental Protection Agency, Washington, DC (United States).
||31 May 1998
||ORNL/CP-95971 ;CONF-980523; AC05-96OR22464;
Thermal Insulation ;
Thermal Conductivity ;
Plastic Foams ;
||Some EPA libraries have a fiche copy filed under the call number shown.
Results are presented on two studies of the effect of aging on the apparent thermal conductivity of polyurethane foam insulation for refrigerators. Both studies are cooperative projects between the Oak Ridge National Laboratory and the Appliance Research Consortium. The first study has been ongoing for four years and involves evaluation of second generation blowing agents: HCFC-141b and HCFC-142/22 blend with CFC-11 for comparison. The second study has recently started and involves third generation blowing agents: HFC-134a, HFC-245fa. and cyclopentane with HCFC-141b for comparison. Both studies consist of periodic thermal measurements on panels made with solid steel and/or plastic skins and a core of foam to simulate refrigerator walls, and measurements on thin slices with cut faces to characterize the core foam. Laboratory data are presented on four years of aging of panels containing second generation blowing agents. Preliminary data are presented for the third generation blowing agents. The data on panels are compared with predictions of computer models of foam aging.