Red Phosphorus Flame Retardant for Polymers

Red phosphorus refractory is widely used to increase the flame retardancy of polymer materials. Its stability and excellent flame retardant effect are known in many fields. Cover red phosphorus as a flame retardant additive, into many polymers, when heated at high temperatures or in case of fire, it can release phosphorylates, interfere with the decomposition of polymer chains, generate a carbon layer that isolates the gas phase, slows down the combustion rate, and inhibits the spread of fire. And red phosphorus is halogen-free, does not release halogen gas, and is more comfortable and environmentally friendly, and is widely favored. Its applications are listed as follows:
First, electrical and electronic components, especially polyamide, polycarbonate, polypropylene and other plastics are the most important. Enclosures, connectors, plugs, cable coverings, switch seats, etc., rely on them to maintain flame resistance and reduce the risk of short circuits or arc breakdown. Red phosphorus is often the main flame retardant in such products, which helps them obtain strict flame retardant certifications such as UL94V-0 and improves electrical safety.
Second, the transportation field. Parts of automobiles, railway cars, aircraft, etc., also contain red phosphorus in polymers, such as interior panels, chassis coverings, electronic circuit parts, etc. This not only reduces weight and saves materials, but also enhances the overall fire resistance of the profile to ensure passenger safety. In view of the high temperature resistance and long-term flame retardant required for transportation products, the advantages of red phosphorus are increasingly obvious.
Third, building materials, such as wire sheaths, floor coverings, insulation boards, pipe coverings, etc., red phosphorus helps them to be non-flammable and reduce the risk of fire. Modern buildings are becoming more and more high-rise, densely populated, and materials have strict flame retardant requirements. The value of red phosphorus flame retardants benefits.
Fourth, home appliances and consumer electronics, shells, films, etc., also use polymer materials containing red phosphorus. This is to ensure its use and safety, prevent electrical failures from causing fires, and take into account health and environmental friendliness.
To sum up, the benefits of red phosphorus refractories cover almost all halogen replacement flame retardant fields of polymer materials, taking into account safety, environmental protection, and efficiency.

Red phosphorus is a simple substance of phosphorus, its color is like cinnabar, and it is loose and flammable. Since ancient times, it has been used as a flame retardant in the process, especially in polymer polymers, and its efficacy is outstanding. There are roughly three reasons for its flame retardancy. First, in the condensed phase, red phosphorus encounters high-temperature seedling smoke and is oxidized to form metaphosphoric acid and polyphosphoric acid. These acidic substances can promote the carbonization of the surface of the polymer material to form a dense carbon shell. The carbon shell isolates oxygen, blocks heat transfer, and makes the material difficult to burn. Second, during the oxidation of red phosphorus, phosphorus dioxide vapor is also released, which reacts with free radicals in the flame area to capture the active free radicals required for combustion, inhibits the chain reaction, and slows down the spread of fire. Third, if the polymer is mixed with an appropriate amount of graft, red phosphorus can cooperate with nitrogen, halogen and other flame retardants to form a dense interface layer, and jointly improve the fire resistance.
When red phosphorus is applied to polyolefin, epoxy resin and other polymer substrates, its decomposition temperature is comparable to the thermal decomposition of the material, and the flame retardant effect is excellent. Because red phosphorus is inorganic, combustion does not produce toxic halogen gases, does not pollute indoor and outdoor air, and is environmentally friendly, it is increasingly important. However, red phosphorus is extremely active and easy to absorb moisture and spontaneous combustion, so it is often microencapsulated with a coated carrier before application. If resin, silicon, and oxide are used as shells, it is not only stable for storage and transportation of red phosphorus, but also easy to mix evenly with polymers. Its compatibility and processability are also improved without damaging the mechanical properties of the parent.
Overall, the flame retardant mechanism of red phosphorus depends on the triple effect of surface carbonization barrier, flame free radical suppression and synergy, which not only ensures flame retardant safety, but also environmental friendliness. Today's material preparation, red phosphorus flame retardant is more and more widely distributed, which is a wonder that the polymer industry relies on.

Red phosphorus is one of the species of phosphorus. It has reddish-brown and delicate properties, and is often used in the flame retardancy of polymer materials. However, its chemical properties are very active, and it is especially necessary to be cautious when applying it. If you do not follow the safety requirements, it is easy to cause disasters and endanger people and facilities. I would like to describe the things that should be paid attention to during its use, which are listed below.
First of all, red phosphorus is easy to oxidize with air, and ignites spontaneously for a long time. It must be stored in a closed container, and it must be isolated from moisture and oxygen. The storage place should be cool, dry, and away from fire and heat sources. If the storage is not good, there is a risk of fire in case of high temperature or friction. For its migration and inversion, use anti-static tools, and avoid iron and friction heat-generating objects. When operating, the operator wears anti-static clothing, protective gloves, goggles and masks to prevent dust inhalation from coming into contact with the eyes.
If red phosphorus dust is mixed with air, it can cause an explosion. When the dust concentration is strictly controlled, it should be well ventilated and should not be operated in a closed space. Reasonable exhaust devices should be prepared in the factory area to remove dust accumulation in time. Discarded red phosphorus should be strictly managed in accordance with safety regulations and should not be dumped at will to prevent pollution of the environment and cause fires.
Once red phosphorus catches fire, it should not be put out with water. It is very dangerous because it burns and meets water or produces toxic phosphine gas. Fire extinguishing equipment such as dry powder and carbon dioxide should be used to stop the fire. In case of fire, the rescuer should wear a gas mask, do not approach an open flame, ventilate quickly, and evacuate unrelated people. At the same time, red phosphorus should not be stored and mixed with strong oxidants, acids, halogens, etc., to prevent chemical reactions from causing trouble.
If red phosphorus touches the skin by mistake, rinse it with plenty of water immediately. If you accidentally take it by mistake, you must seek medical attention and explain the cause of poisoning. As for the containers and utensils after use, they should be properly cleaned or sealed to prevent their residues from hurting people.
Therefore, when using red phosphorus to resist flame, you should be vigilant at all times, follow the norms, and do not take chances. In order to make safe use of its performance, protect people and industries, and avoid future problems.

Red phosphorus is an allotrope of phosphorus, which has stable properties and is difficult to dissolve in water. It is mostly used as a flame retardant polymer. Red phosphorus flame retardant applied to polymers can change its characteristics in many aspects. When red phosphorus is heated, phosphoric acid and polyphosphoric acid are formed, which can form a dense carbon layer on the surface of the polymer, inhibit the contact between oxygen and heat, and inhibit the spread of combustion. The flame retardant mechanism it provides promotes carbonization on the one hand, and shields heat and oxygen on the other hand, so the fire is not easy to spread. Red phosphorus has good compatibility with polymers. Adding an appropriate amount and dispersing evenly can significantly improve the flame retardancy of materials.
However, red phosphorus is not without effect. Although its chemical properties are more stable than yellow phosphorus, when wet or high temperature, or during processing, it is easy to form acidic products with oxygen and nitrogen in polymer materials. If it is not properly coated, it can cause polymer degradation, resulting in a decline in mechanical properties. Also red phosphorus has a brown-red color, making it difficult to prepare light-colored products, which affects the appearance. In addition, if red phosphorus is not perfectly coated, it is easy to evaporate into China, and there is a risk of gradual deterioration of performance after long-term use or in high-temperature environments.
Polymers after red phosphorus flame retardant have common mechanical properties that decrease, such as slightly reduced tensile strength and impact toughness, especially high additive content. Due to its large particle size or uneven dispersion, defects are formed, which affect the structural compactness of the polymer. In addition, red phosphorus interacts with some additives, which affects the stability of the composite system. However, after surface coating and high dispersion modification, the adverse effects can be greatly reduced, especially when it is shared with some synergistic agents, taking into account the flame retardant efficiency and comprehensive properties.
To sum up, red phosphorus flame retardant polymers are beneficial to improve flame retardant properties, inhibit flame expansion, and prolong escape opportunities. However, there are certain compromises in mechanics, processing, and appearance. If the process is properly controlled, the advantages can outweigh the disadvantages, making it an important material in the field of flame retardancy of polymer materials.

The red of phosphorus is safe in nature and can resist fire, and has been favored by technology for a long time. Its function is to inhibit the combustion of polymers, and the products used can greatly increase their safety. However, the use of this special material, the method and quantity are different. If there is a slight deviation, the effectiveness will be difficult to recognize, resulting in poor quality.
Its usage can be divided into two ways. First, the direct method is also; the red phosphorus powder is evenly mixed into the polymer masterbatch and mixed to form. If you want to disperse more evenly, you often need to use a dispersant or use it in a high-speed mixing machine. Second, the coating method is also; it is wrapped in resin or wax, so that the red phosphorus is wrapped in particles to avoid contact with air and reduce precipitation or failure. The choice of coating particles, or polyolefins, or epoxies, is made according to the performance of the product. However, although the coating can prevent moisture and oxygen, it increases the process cost, depending on the situation.
The dosage depends on the demand. However, the amount of large-rate polyolefins, polyvinyl alcohols, polypropylene and even epoxy resins is usually 1% to 7% of the quality. If you want to meet the high flame retardant level, such as UL-94 V-0, the dosage can be up to 10% or more. However, red phosphorus is not as fierce as white phosphorus after all. It has excellent heat resistance and high flame retardant efficiency. Less dosage is enough to achieve work. It is necessary to cooperate with additives such as nitrogen-based and amine-based to shield smoke and enhance fire suppression, but the dosage should not be too much, lest the product will become brittle, the color will darken, the mechanical properties will decline, and even spontaneous combustion will occur due to the precipitation of red phosphorus.
According to the process, the raw materials are often premixed and dried into the extruder, and then blended with the main material to ensure uniform distribution and avoid high temperature decomposition. Extrusion and injection molding are suitable. The thickness of the product should also be considered. The demand for thin walls should be increased, and the thickness should be slightly reduced.
In short, the benefits of red phosphorus flame retardancy can only be achieved if the usage method and dosage are in line, supplemented by suitable additives and coating measures, so that the polymer can be at ease with fire and has a long quality. The multi-end of the production method must be explored and the choice of quantity must be based on experience. Such products can have excellent flame retardancy and undiminished quality.