Flame Retardant Mechanism of Red Phosphorus Flame Retardant
Red phosphorus is decomposed by heat and can react with oxygen in the surrounding air to produce oxyphosphoric acid. This oxyacid has better water absorption, allowing the surface of the burning polymer to be dehydrated and carbonized to form a carbonized layer, which not only isolates the polymer and reduces combustibility The release of sexual volatile components also has endothermic properties, which reduces the heat of oxidation on the surface of the polymer and realizes the flame retardancy of the condensed phase.

The pyrolysis product of red phosphorus PO·radical enters the gas phase, it can also capture a large amount of H·, HO·radical in the combustion flame, cut off the flame oxidation chain reaction, and achieve the purpose of gas phase flame retardancy.

Red phosphorus flame retardant and flame retardant properties
Red phosphorus can easily absorb moisture in the air, and produce H3PO4, H3PO3, H3PO2 and other substances, which make red phosphorus sticky and lose its fluidity, and the phosphoric acid produced is easier to absorb water. If red phosphorus is present in the polymer material products, the red phosphorus absorbs moisture and oxidizes, which will cause the urban gloss and original performance of the product surface to corrode, and slowly corrode to the inner layer. At the same time, the generated oxyacid will also corrode the processing equipment.
The compatibility of red phosphorus with resin is poor, and segregation and sedimentation will occur, which will increase the viscosity of the resin, which will bring difficulties to the casting, impregnation and operation of the resin, and will also cause the performance of synthetic materials to decrease.
Prolonged contact of red phosphorus with air will not only generate phosphorus oxyacids, but also release highly toxic PH3 gas, which is harmful to the environment and human body.
The hygroscopicity and instability of red phosphorus have an adverse effect on the physical properties of plastic products, especially the leakage of weak current components and the insulation of high voltage components.
The purple-red color of red phosphorus itself will make the product color.
Red phosphorus is easily ignited by impact, and dry red phosphorus dust has the risk of burning and explosion.
Red phosphorus flame retardant is relatively environmentally friendly in the application process, and it has excellent flame retardant effect, which is a rare flame retardant substance.