Hydrofluoroolefin

Unlike traditional hydrofluorocarbons (HFCs) and chlorofluorocarbons (CFCs), which are saturated, HFOs are olefins, otherwise known as alkenes.

[1] This quick reactivity prevents them from reaching the stratosphere and participating in the depletion of good ozone, leading to strong interest in the development and characterization of new HFO blends for use as refrigerants.

[2] Many refrigerants in the HFO class are inherently stable chemically and inert, non toxic, and non-flammable or mildly flammable.

They have also been adopted as blowing agents, i.e. in production of insulation foams, food industry, construction materials, and others.

However, HFOs degrade to produce trifluoroacetic acid, a persistent toxic chemical which can lead to acidification of water bodies, and which can accumulate in wetlands, a sensitive ecosystem.