Britannica Sources used in this answer

Why were chlorofluorocarbons first used as refrigerant gases?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

organohalogen compound Vinyl chloride is an organohalogen compound that has important industrial applications. When treated with certain catalysts, vinyl chloride monomers undergo polymerization and form the larger compound known as polyvinyl chloride, or PVC. PVC is used in the manufacture of numerous products, including packaging films and water pipes.

Chlorofluorocarbons (CFCs) were first developed and adopted as refrigerants in the 1930s because they offered a combination of properties that made them ideal for use in residential refrigerators and air-conditioning systems.123

Specifically, they were valued for being:
* Nontoxic and nonflammable: Unlike earlier refrigerants, they did not pose a fire hazard or present significant health risks to users.123
* Odourless: They did not release detectable smells while circulating through cooling systems.23
* Chemically stable: Their inert nature made them reliable for industrial and commercial applications.3
* Physical versatility: They possess low boiling points, low surface tension, and low viscosity, allowing them to be easily converted between liquid and gaseous states.13

While these properties made them highly effective for cooling, it was later discovered that their stability allowed them to reach the stratosphere, where they contribute to the depletion of the ozone layer. This environmental impact eventually led to the global phase-out of CFCs under the Montreal Protocol.134