Flameout principle of flame retardant1. Produce a gas that can smother the flame. For example, antimony trioxide, when it encounters HCL due to combustion in PVC, reacts to form a suffocating gas, that is, nitrogen oxides of antimony.
2. The heat generated during combustion is absorbed, and the cooling slows down the burning rate. For example, aluminum hydroxide, which contains up to 34% of the chemically associating water in the molecule, is stable at the processing temperature of most plastics, but begins to decompose at temperatures above 200 °C, releasing water vapor. And each time a gram of aluminum hydroxide is decomposed, it absorbs 36 kilocalories.
3. A layer of oxygen barrier is provided. For example, a phosphide formed when a phosphate flame retardant is burned is an oxygen barrier coating.
4. A free radical that reacts with the plastic is formed to provide a flame retardant effect. Their reaction products with plastics have extremely poor combustion properties.
Novisa supply Sb2O3, Phosphorus flame retardant.