Halogen-free flame retardant (AZO), also known as halogen-free low smoke environmental protection flame retardant or green environmental protection inorganic flame retardant material, is a non-toxic, non-corrosive, environmental protection type of new flame retardant material, with low smoke (≤25mg/m³), high oxygen index and excellent flame resistance. The following is a detailed explanation of halogen-free flame retardants:
First, the main components and types
Halogen-free flame retardants are mainly composed of metal oxides, and add a variety of inorganic substances and organic compounds. It does not contain halogens and therefore does not produce toxic gases when burned. Common types of halogen-free flame retardants on the market mainly include:
Inorganic compounds containing nitrogen, such as magnesium chloride, aluminum hydroxide, etc.
An inorganic compound containing sulfur, such as sodium sulfide.
Inorganic compounds containing phosphorus.
Boron-containing silicates and other types of inorganic substances.
Phosphorus compounds, such as ammonium polyphosphate salts, polyether amine salts and organic fluorides, etc.
Silicon flame retardants and nitrogen flame retardants are several new types of halogen-free flame retardants.
Second, mechanism of action
The main action mechanism of halogen-free flame retardants is the formation of porous carbon layer. Halogen-free flame retardants are mostly hydrates of metal oxides, which can absorb a lot of heat during endothermic decomposition and dehydration, inhibit the temperature rise of the burned part and its vicinity, and the decomposed water vapor in turn prevents the release of combustible gases. In addition, halogen-free flame retardants can also play a role through the condensed phase, such as the expansion of halogen-free flame retardants in the combustion process will produce water vapor and non-combustible gas, so that the system expansion foam, the formation of porous foam carbon layer, so as to isolate oxygen, to achieve the purpose of flame retardant.
Third, advantages and characteristics
Halogen-free flame retardants have the following advantages and characteristics:
Environmental protection and non-toxic: no halogen, combustion will not produce toxic gases and corrosive gases, harmless to the human body or minimal harm, will not cause pollution to the environment.
Small amount of smoke: The smoke generated when burning is extremely low toxicity, which is conducive to fire rescue and personnel evacuation.
Excellent performance: has excellent flame retardant performance, can effectively inhibit the spread of fire.
Low price: Inorganic flame retardants from a wide range of sources, the price is relatively low.
Good compatibility: After special surface treatment, it is easy to disperse in plastic materials, does not precipitate, and has good flame retardant effect.
Fourth, application field
Halogen-free flame retardants have a wide range of applications, including:
Flame retardant treatment of wire and cable.
Fire protection of electronic components and precision instruments.
The insulation layer of the car wire harness prevents fire caused by leakage.
Fire insulation system for building materials.
The line connection in household appliances and the connection line between the computer motherboard and the display.
In general, halogen-free flame retardant is a kind of flame retardant material with excellent performance, environmental protection and non-toxic, and has a wide range of application prospects in various fields. As people’s attention to environmental protection and safety continues to increase, the market demand for halogen-free flame retardants will continue to grow.
