Inorganic flame retardant
Different flame retardants have different requirements for use. Different flame retardants have different flame retardant effects; different flame retardants have different effects on the environment; what are the similarities and differences between inorganic flame retardants and halogen-free flame retardants? Inorganic flame retardants: generally refers to inorganic compounds that have flame retardant or smoke suppression effects in the formulation added to the polymer. There are mainly hydroxides (aluminum hydroxide, magnesium hydroxide), red phosphorus, tin, and borate (zinc borate). What are the advantages and disadvantages of inorganic flame retardants? Advantages: In addition to flame retardants, inorganic flame retardants also have a smoke suppression effect and can inhibit the formation of hydrogen chloride. Because of their non-toxic and non-corrosive properties, they are widely used. In today's increasingly stringent environmental protection requirements, inorganic flame retardants show strong competitiveness and development potential. Disadvantages: Inorganic flame retardants usually have relatively low flame retardant performance, and need to increase the amount of addition.
Halogen-free flame retardant
Halogen-free flame retardant: The halogen-free flame retardant does not contain halogen and has a good flame retardant effect. Halogen-free flame retardant additives are mainly composed of phosphorus compounds and metal hydroxides. These two types of compounds are non-volatile and will not generate corrosive gases during the combustion process, and are called non-polluting flame retardants, and there are several new types of halogen-free flame retardants, such as silicon-based flame retardants and nitrogen-based flame retardants. Flame retardant. These new halogen-free flame retardants have become new products that meet the development trend of international flame retardant standards.
The difference between halogen-containing flame retardants and halogen-free flame retardants:
- The inorganic flame retardant does not contain carbon and its carbon compounds.
- The inorganic flame retardant may contain halogen elements.
- Halogen-free flame retardants are flame retardants that include both halogen-free and inorganic standards. Halogen-containing flame retardants and halogen-free flame retardants
Halogen-containing flame retardants refer to halogen-containing polymers or flame retardants mixed with halogen-containing flame retardants, mainly including antimony trioxide and decabromodiphenyl ether, also known as bromine antimony flame retardants, It has excellent flame retardant properties and has been widely used as a hindered material.
However, when a fire occurs, the materials produced using this halogen-containing flame retardant will generate a large amount of smoke and toxic corrosive hydrogen halide gas, which will cause secondary harm.
In February 2003, the European Union issued two directives, namely WEEE and RoHs. WEEE is an explanatory directive on the recycling of waste electrical and electronic equipment. Rohs is a directive that restricts and prohibits the use of certain toxic and hazardous substances and elements in electrical and electronic equipment.
In August 2004, these two directives were converted into the laws (regulations) of the 15 EU member states. Western Europe began to implement new flame retardant classification methods and testing standards in wire and cable, building materials, coatings, and other industries.
China has also begun to apply national standards for the combustion performance levels of building materials and products. China’s flame retardant performance levels and national standards have many of the same characteristics as the new standards in Western Europe. They are: focusing on the fire growth rate, heat release rate, smoke generation, and the corrosion and toxicity standards of combustion products.
In order to pass these new standards, traditional halogen-based flame retardant materials (such as antimony trioxide) seem to be powerless. Inorganic flame retardants are composed of high-temperature-resistant solutions added to ultrafine inorganic metal oxides.
Inorganic flame retardants are mainly in the form of simple substances or compounds by adding inherently flame-retardant inorganic elements to the flame-retardant substrate, and fully mixed with the high polymer in a physically dispersed state, and pass through the physically dispersed state or the high polymer.
In the gas phase or the condensed phase, physical changes play a flame retardant effect. The research and development of wood flame retardants mainly include metal Mg, Al, Ca, non-metallic B, Si, N, P, Sb, halogen, and transition elements Mo, V, Fe, etc. Inorganic flame retardants are mainly metal hydrates, red phosphorus, boron compounds, antimony compounds, etc.
Inorganic flame retardants have good thermal stability, non-volatility, long-term effect, low price, etc., and have been widely used.