Improved Aging CO2 Blown Foam for Refrigerators/Freezers

An industrial trial has been conducted to evaluate aging and energy consumption performance of a new, slow-aging CO2 blown PU foam. A PETG barrier film laminated on the liner sheet and plastic encapsulated powder vacuum panels (PVP's) were included in the trial matrix to measure their impact on aging and energy consumption, respectively. The CO2 foams produced at 2.31 pounds per cubic foot (2.31 pcf) minimum fill density (37 kg/m3 in metric units) showed excellent structure, lower k-factor and a 10-fold retarded aging effect with respect to conventional CO2 foams. Using current HCFC-141b technology as a reference, initial energy consumption was 15% to 20% higher without vacuum panels but nearly 10% lower with vacuum panels. Within the one year measurement period available so far, aging effects are virtually negligible for the new CO2 foam which is attributed to the combined action of barrier liner and slow aging CO2 foam. The underlying mechanism for the observed excellent performance is attributed to a lack of condensation effects under service conditions which are always associated with the use of the usual high-boiling blowing agents, such as HCFC-141b and cyclopentane.