HFC-365mfc/134a as a Blowing Agent for Spray Foam Systems to Substitute HCFC-141b

A pilot plant for HFC-365mfc is on stream since 1.1.2000, and the full commercialization of HFC-365mfc is scheduled for 2002/2003. HFC-365mfc/134a blend 93/7 is an option for spray foam and for pour-in place foam systems as a substitute for HCFC 14 lb. The blend HFC-365mfc/134a 93/7 has no flash point but has flammability limits in air, which has already been experienced with HCFC 14 lb. This particular blend is a mixture, so there are handling differences when compared to HCFC-141b. We report about handling and safety aspects and discuss the minimum ignition energy of the vapor phase in comparison to 141b and pentane. For a spray foam system prepared with HFC-365mfc/134a 93/7 the effect of blowing agent concentration on system vapor pressure is described. We discuss the evolution of the resulting atmosphere above a pre formulated system in a closed system, the vapor concentration during spraying and the resulting ratio of the blowing agent blend in the cells of a sprayed foam. Our study will answer frequently asked questions about the application of HFC-365mfc/134a for spray foam systems and aim to provide the market construction foam industry with a solution for all markets.