The standards for energy efficiency have been constantly rising, and at the same time the rigid polyurethane foam industry is also facing ever increasing pressure to address climate change by eliminating global warming substances. Blowing agents are vital foam components and are responsible for the outstanding thermal performance of PU foams that are commonly used for thermal insulation in appliances and residential and commercial buildings.
To meet these challenges, Arkema is investigating a new range of blowing agents, the AFA series, designed for most PU applications including appliances, pour-in-place (PIP), spray, and polyisocyanurate (PIR) boardstock. AFA blowing agents are both liquid and gas, and have very low global warming and negligible ozone depletion potential.
The focus of this study was to evaluate solutions based on AFA-L1, which is a liquid under ambient conditions and is a candidate for replacement of the hydrofluorocarbon HFC-245fa and hydrocarbons. Using other blowing agents such as cyclopentane, HFC-134a, 245fa, and HCFC-141b (a hydrochlorofluorocarbon) as references, AFA-L1 was evaluated using an Edge Sweets high-pressure foam machine. AFA-L1 displayed a similar blowing efficiency, provided some improvement in dimensional stability, and an advantage in initial kfactor versus HFC-245fa and hydrocarbons. The solubility of AFA-L1 based agents in various polyols, and its compatibility with materials such as plastics, elastomers, and metals,…