Retardant

A retardant is a substance used to slow down or inhibit a specific chemical reaction or physical process. The most common usage refers to fire retardants, which are chemicals applied to materials to prevent or delay the spread of fire. These work by interfering with the combustion process, either by cooling the fuel, forming a protective char layer, or releasing flame-quenching gases.

Fire retardants are crucial for enhancing safety in various industries. They are added to materials like textiles, plastics, wood, and building materials to meet fire safety standards. They can be categorized as additive, where the retardant is mixed into the material during production, or coating, where it is applied to the surface.

Beyond fire safety, the term has broader applications. In chemistry, a retardant can slow the cure rate of adhesives or polymers, giving workers more time for application. In materials science, rust retardants, or corrosion inhibitors, are used to protect metals from oxidizing. Some agricultural chemicals act as growth retardants to control plant size.

While highly effective, the use of certain chemical retardants, particularly some brominated flame retardants, has raised environmental and health concerns due to their persistence and potential toxicity. This has led to increased research into safer, more environmentally friendly alternatives.