Comparative Evaluations of Alternative Blowing Agent Systems in Appliance Foams and Cabinets

The Manufacture of HCFC-141b (used as an insulation foam blowing agent) will be discontinued in the United States on December 31, 2002. In addition, the United States appliance industry must meet a U.S. Department of Energy (DOE) requirement for energy redaction of up to 30% (compared to 1993 standards) by July of 2001. Feasibility testing of alternate blowing agent foams was previously reported by the AHAM Industry/Government CFC Replacement Consortium and indicated a 6-10% increase in energy with cylopentane blown foams. The evaluations of HFC-245fa and HFC-236ea blown foams in non-optimized systems also had higher k-factors than HCFC-141b blown foams. The Dow Chemical Company and Maytag-Galesburg Refrigerator Products have conducted additional blowing agent evaluations on a newly designed top freezer cabinet. HFC-245fa, HFC-236ea and cyclopentane have been evaluated and compared to HCFC-141b in rigid appliance systems utilized today. Several new polyols, surfactants and catalysts were utilized in this formulation design experiment. The performance of each of the alternative blowing agents was evaluated in laboratory samples and in refrigerator/freezer cabinet foaming trials.