What is Flame retardants and its application?

What is Flame retardants and its application?

Flame retardants, functional additives that endow flammable polymers with flame retardancy, are mainly designed for the flame retardancy of polymer materials; there are many types of flame retardants, which are divided into additive flame retardants and reactions according to the method of use Type flame retardant.

The additive flame retardant is added to the polymer by mechanical mixing method to make the polymer flame retardant. At present, the additive flame retardant mainly includes organic flame retardant and inorganic flame retardant, halogen flame retardant (organic flame retardant). Chloride and organic bromide) and non-halogen. Organic is some flame retardants represented by bromine series, phosphorus nitrogen series, nitrogen series and red phosphorus and compounds. Inorganic is mainly antimony trioxide, magnesium hydroxide, aluminum hydroxide, silicon series and other flame retardant systems.

Reactive flame retardants are used as a monomer to participate in the polymerization reaction, so the polymer itself contains flame retardant ingredients. Its advantage is that it has less impact on the performance of polymer materials and has long-lasting flame retardancy.

In order to increase the flame resistance of polymer materials, it is mainly used for polymer materials such as plastics, rubber, fibers, etc., and most of these materials are combustible. Especially for plastics, if it is to be used in transportation, construction, electrical equipment, aviation, space flight, etc., it is urgent to solve the problem of its resistance to combustion. The use of flame retardants should generally meet the following conditions: do not reduce the physical properties of polymer materials, such as heat resistance, mechanical strength, and electrical properties; the decomposition temperature should not be too high, but it cannot be decomposed at the processing temperature; durability Good; good weather resistance; low price. [1]

Generally speaking, organic flame retardants have a good affinity. In plastics, brominated flame retardants have an absolute advantage in organic flame retardant systems. Although there are many criticisms on environmental protection issues, it has been difficult to be replaced by other flame retardant systems. .

Among the non-halogen flame retardants, red phosphorus is a good flame retardant, which has the advantages of small addition, high flame retardant efficiency, low smoke, low toxicity, and wide use; red phosphorus and aluminum hydroxide, expandable graphite Inorganic flame retardants are compounded and used to make composite phosphorus/magnesium; phosphorus/aluminum; phosphorus/graphite and other non-halogen flame retardants. The flame retardant dosage can be greatly reduced, thereby improving the processing performance and physical and mechanical properties of plastic products . However, ordinary red phosphorus is easy to oxidize and absorb moisture in the air, easily cause dust explosion, difficult to transport, poor compatibility with polymer materials and other defects, so the scope of application is limited. In order to make up for this shortcoming, a microcapsule coating process can be used to make it into microencapsulated red phosphorus. In addition to overcoming the inherent disadvantages of red phosphorus, the microencapsulated red phosphorus has high efficiency, low smoke, no toxic gas generated during processing, and its dispersibility, physical, mechanical properties, thermal stability and flame retardancy are improved. improve.