As a common type of flame retardant, nitrogen-based flame retardants are widely used in the flame retardant treatment of polymer materials. Its flame retardant mechanism is mainly based on the release of nitrogen, ammonia and other gases, dilute the concentration of flammable gases, and inhibit flame combustion at the same time, so as to achieve the purpose of flame retardant.
At present, the common nitrogen-based flame retardants on the market are mainly as follows:
1.Nitrogen compound flame retardant.
Nitrogen compound flame retardant is a class of nitrogen-containing organic compounds, and its flame retardant mechanism is mainly through decomposition to produce nitrogen and dilute the concentration of flammable gas, thereby playing a flame retardant role. Common flame retardants for nitrogen compounds include urea, melamine, melamine, etc. These flame retardants can decompose to produce nitrogen when heated, and at the same time inhibit flame combustion, so as to achieve the purpose of flame retardant.
2.Phosphorus and nitrogen-containing compound flame retardants.
Phosphorus and nitrogen compound flame retardant is a class of compounds containing phosphorus and nitrogen at the same time, and its flame retardant mechanism is similar to that of nitrogen compound flame retardant, which also dilutes the flammable gas concentration by releasing nitrogen, ammonia and other gases, so as to achieve the purpose of flame retardant. Common flame retardants containing phosphorus and nitrogen compounds include aluminum hypophosphite, ammonium hypophosphite, etc. These flame retardants can decompose to produce gases such as nitrogen and ammonia when heated, and at the same time inhibit flame combustion, so as to achieve flame retardant purposes.
3.Flame retardants of nitrogen-containing silicone compounds.
Nitrogen-containing silicone compound flame retardant is a class of organic compounds containing nitrogen and silicon elements, and its flame retardant mechanism is mainly through the formation of a dense siloxane film on the surface of the material, which plays the role of isolating oxygen, thereby inhibiting flame combustion. Common flame retardants for nitrogen-containing silicone compounds include polyurethane siloxanes, polyurethane silanes, etc. These flame retardants can form a dense siloxane film when heated, which plays the role of isolating oxygen, so as to achieve the purpose of flame retardant.
4.Nitrogen-containing inorganic salt flame retardant.
Nitrogen-containing inorganic salt flame retardant is a class of inorganic salts containing nitrogen, and its flame retardant mechanism is mainly through the formation of a layer of molten glass-like substance on the surface of the material, which plays the role of isolating oxygen, thereby inhibiting flame combustion. Common nitrogen-containing inorganic salt flame retardants include melamine, cyanurate, ammonium tripolyphosphate, etc. These flame retardants can form a layer of molten glass-like substance when heated, which plays the role of isolating oxygen, so as to achieve the purpose of flame retardant.
To sum up, there are many types of nitrogen-based flame retardants, and their flame retardant mechanism is mainly to dilute the concentration of flammable gases or form a dense layer of substances to isolate oxygen, thereby inhibiting flame combustion. Different nitrogen-based flame retardants are suitable for different types of materials and different processing processes. When using nitrogen-based flame retardants, the appropriate type and amount should be selected according to the specific situation to achieve the best flame retardant effect.