Introduction of three commonly used PP plastic flame retardants-Halogen Free Flame Retardant for PP

1. Brominated flame retardant

Most brominated flame retardants will decompose at 200-300°C. This temperature range is also the decomposition temperature range of polypropylene. Therefore, when polypropylene is decomposed by heat, brominated flame retardants will also begin to decompose and can capture them. Free radicals generated by the degradation reaction, thereby delaying or terminating the combustion chain reaction.

At the same time, the released HBr itself is a kind of flame-retardant gas. This gas has a high density and can cover the surface of the material to block the combustible gas on the surface and inhibit the burning of the material.　

The main disadvantage of bromine-based flame retardants is that they reduce the anti-ultraviolet stability of the flame-retardant substrate, and generate more smoke, corrosive gases and toxic gases during combustion, which limits their application.　　

2. Phosphorus-nitrogen flame retardant

Phosphorus-nitrogen flame retardant is also called intumescent flame retardant.Halogen Free Flame Retardant for PP

 ， When the polymer containing this kind of flame retardant is heated, a uniform carbon foam layer can be formed on the surface, which can heat insulation, oxygen and smoke. It can prevent the phenomenon of droplets, so it has good flame retardant properties. Intumescent flame retardant systems generally consist of three parts: acid source (dehydrating agent), carbon source (carburizing agent) and gas source (nitrogen source, foaming source). Intumescent flame retardants play a flame retardant role in the cohesive phase mainly by forming a porous carbon foam layer. Phosphorus-nitrogen flame retardants have the advantages of halogen-free, low smoke and low toxicity.　　

3. Phosphorus flame retardant

Phosphorus-based flame retardants have a flame retardant effect by promoting dehydration and carbonization during the initial decomposition of the polymer. This dehydration carbonization step must rely on the oxygen-containing groups of the polymer itself, and for polymers with oxygen-containing groups in their structure. Their flame retardant effect will be better.