Halogen-free flame retardants currently mainly include organic and inorganic, halogen and non-halogen. Organic is some halogen-free flame retardants represented by bromine, nitrogen and red phosphorus and compounds. Inorganic is mainly flame retardant systems such as antimony trioxide, magnesium hydroxide, aluminum hydroxide and silicon.
Generally speaking, organic flame retardants have a good affinity in plastics. Bromine-based halogen-free flame retardants occupy an absolute advantage in organic flame retardant systems. Although they are "disputable" on environmental issues, it has been difficult to have other halogen-free flame retardants Agent system.
Among the non-halogen halogen-free flame retardants, red phosphorus is a better halogen-free flame retardant, which has the advantages of less addition, high flame retardant efficiency, low smoke, low toxicity, and wide range of uses; red phosphorus and aluminum hydroxide , Expanded graphite and other inorganic halogen-free flame retardants are used in combination to make composite phosphorus / magnesium; phosphorus / aluminum; phosphorus / graphite and other non-halogen halogen-free flame retardants. Improve the processing performance and physical mechanical properties of plastic products. However, the common red phosphorus is easy to oxidize and absorb moisture in the air, which is easy to cause dust explosion, difficult transportation, and poor compatibility with polymer materials. Its application range is limited. In order to make up for this deficiency, and to expand the application scope of red phosphorus, we adopted the advanced foreign microcapsule coating process to make it into microencapsulated red phosphorus. In addition to overcoming the inherent shortcomings of red phosphorus, microencapsulated red phosphorus has high efficiency, low smoke, does not produce toxic gases during processing, and its dispersibility, physical, mechanical properties, thermal stability and flame retardant properties are improved and improve.