With the expansion of the application of polymer composite materials and the increase in the amount of use, the application of flame retardant materials and flame retardant technology have also achieved certain development and progress. Phosphorus-based flame retardants are widely used due to their wide variety and excellent flame retardant properties. In the future research on phosphorus-based flame retardants, the development direction of flame retardants with high thermal stability and good compatibility should be more inclined.
Flame retardants are additives used to prevent materials from being ignited and inhibit the spread of flames. They are mainly used for flame retardant synthetic and natural polymer materials, and are an indispensable chemical material in our lives. Since the widespread use of organic synthetic polymer materials, mankind has begun to face new fire threats. At present, the form of global fires is very serious. Therefore, flame retardants, such as chemical additives, are particularly important.
(1) Types and basic requirements of flame retardants:
According to the relationship between the flame retardant and the flame retardant, the flame retardant can be divided into two categories: additive type and reactive type. The former is only physically dispersed in the substrate and is mostly used in thermoplastic polymers. The latter is used as a monomer or auxiliary reagent to participate in the reaction of synthesizing a polymer, and finally becomes a structural unit of the polymer, which is mostly used in thermosetting polymers.
According to the flame retardant elements, commonly used flame retardants are divided into halogen series, organic phosphorus series and halogen-phosphorus series, nitrogen series, phosphorus-nitrogen series, antimony series, aluminum-magnesium series, inorganic phosphorus series, boron series, silicon series , Molybdenum, etc. There is also a type of intumescent flame retardant and a nano-inorganic substance, which can form a flame-retardant polymer/inorganic nano-composite material with a series of polymers.
(2) What are the basic elements of flame retardants:
(1) High flame retardant efficiency
(2) It should have the following ecological and environmental protection characteristics (1. Harmless to humans, animals and plants 2. Difficult to migrate 3. Less toxic or corrosive gases released during thermal cracking and combustion 4. Easy to recycle, no deterioration or Minor deterioration of the performance of mechanical recycling products 5. Compatible with the environment)
(3) Good compatibility with the flame retardant substrate
(4) has sufficient thermal stability
(5) It will not deteriorate the processing performance of the flame retardant substrate too much.
(6) Has acceptable light stability
(7) The source of raw materials is sufficient, the manufacturing process is simple, and the price can be accepted by users
It is worth noting that an ideal flame retardant can best meet the above conditions, but this is almost impossible. Therefore, when choosing a practical flame retardant, most of them are on the premise of meeting the basic requirements, and compromise between other requirements and obtain the best comprehensive balance.
Now, it is increasingly recognized that the use of flame retardant materials is one of the strategic measures to prevent and reduce fires, and the practice in some countries has also proved this. There is no doubt that the research, production and application of flame retardants and flame retardant materials are important measures related to "environment and human beings", and "flame retardants" will be accepted by more and more people.
