ABSTRACT
The objective of flame-retarding thermoplastics is to increase the resistance of a material to ignition and, once ignited, to reduce the rate of flame spread (slow burning). The product does not become noncombustible, but use of a flameretardant* additive may prevent a small fire from becoming a major catastrophe. The primary flame retardants used to accomplish this objective are halogen-and phosphorus-containing organic compounds. Antimony oxide is generally required as a synergist for halogen compounds. Inorganic compounds containing high concentrations of water of hydration, such as alumina trihydrate and magnesium hydroxide, are also used. The type of flame retardant and the quantity needed to meet specific objectives depend on the specific polymer. Additive as well as reactive flame retardants are available commercially. The latter type are used mainly in thermoset resins.
