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Flame retardant of PVC plastics
2017-11-6 11:42:53
Flame retardant of PVC plastics
Flame retardant is a kind of additives that can prevent the polymer material from being ignited or inhibit flame propagation. In early 1950s, with reactive monomer chlorendate developed flame retardant unsaturated polyester, opens up a new way in the field of the research work of flame retardant, then flame retardant containing bromine and phosphorus monomer emerging new.
In 60s, many kinds of flame retardants for PVC plastics were developed. From the early 70s to the middle of 80s, the production and application of PVC flame retardant developed vigorously.
Since 1986, the flame retardant has been carried out and the toxicity of polybrominated diphenyl ether type two environmental problems of flame retardant disputes, promote the new substitute of decabromodiphenyl oxide (including intumescent flame retardant and halogen-free flame retardant) research and development.
However, with the improvement of flame retardant requirements and the enhancement of environmental protection consciousness, the halogen-free, smoke suppression and attenuation of flame retardants have become the frontier topics in the research field of PVC flame retardants at present and in the future. How to develop a new flame retardant with better performance, better effect and more environmental protection? A lot of research work has been carried out in this field at home and abroad. The new flame retardant in twenty-first Century will be halogen free, high efficiency, low smoke, low toxicity, multi-functional composite flame retardant.
At present, the most representative halogen-free inorganic metal compound flame retardants are aluminum hydroxide (ATH) and magnesium hydroxide (MDH). ATH with flame retardant and smoke, filled with three functions, plus it is not volatile, non-toxic, and can produce a synergistic effect with a variety of substances, so its consumption has maintained a high growth rate, which has remained at more than 40% in the proportion of the total amount of flame retardant in. However, ATH usually needs more than 50% to show a good flame retardant effect.
In order to overcome this shortcoming, on the one hand can be used to develop improved granulation technology, ultra fine direction, make size distribution narrowed; on the other hand, the particle surface treatment, silane coupling agent, titanate, paraffin, stearic acid salt and organic silicon to improve its mechanical strength, also can be used to improve coating with a large molecular bonding technology and methods to improve its performance.
Tris(2-chloroisopropyl)Phosphate(TCPP)
Tris(2-chloroisopropyl)Phosphate(Flame retardant TCPP) is a colorless or yellowish oily liquid. It is soluble in benzene, alcohol, carbon tetrachloride and other organic solvents, but insoluble in water and aliphatic hydrocarbons. Its relative density is 1.27-1.31, refractive index is 1.4916 ( 21.5 ), viscosity is 58mm2 / S, chlorine content is 32.8%, and phosphorus content is 9.5%. As the molecule contains phosphorus and chlorine element simultaneously, its flame retardant properties is significant, as well as the plasticization, damp-proof, antistatic effects and so on. Tris(2-chloropropyl) phosphate (TCPP) is an additive flame retardant.
The product is used for the soft / hard polyurethane foam, with thermal and hydrolytic stability good, especially suitable for ASTME84 (Level 11) foam, with low viscosity unsaturated polyester resin in low temperature application and phenolic plastics at. This product is also used to grab the foam sealant and sheet production. For polyvinyl chloride, polystyrene, phenolic resin, acrylic resin and rubber, coating, flame retardant, also used for soft and hard polyurethane foam, epoxy resin, polystyrene, cellulose acetate, ethyl cellulose tree and phenolic plastics, polyvinyl acetate and gun type foam sealant production. Particularly recommended for rigid polyurethane foam has excellent thermal and hydrolytic stability is particularly suitable for ASTM84 (II), compound for polyurethane foam and unsaturated resin and phenolic plastics.
The flame retardant mechanism of ATH is: (1) add ATH to the polymer, reducing the concentration of combustible polymers; (2) to dehydration, heat absorption and inhibition of polymer in 250 degrees Celsius temperature; (3) decomposition of water vapor dilution of the concentration of combustible gas and oxygen, can prevent combustion; (4) in the formation of combustible surface Al2O3, stop burning. MDH is a kind of additive inorganic flame retardant which is developed rapidly. It is low smoke, non-toxic, and can neutralize the acid and corrosive gas in combustion process.
Its flame retardant mechanism is similar to that of ATH. Compared with ATH, MDH high decomposition temperature 100 ~ 150 degrees, can be used for flame retardant finishing temperature higher than 250 DEG C, engineering plastics, and also promote charring effect, but to reach a certain amount of flame retardant effect, in more than 50%, has great influence on the properties of materials. In order to reduce the amount of MDH in the polymer, one method is to make the MDH particles fine, and the other is to modify the surface of MDH by coating technology to improve its compatibility with the polymer.
Expandable graphite is a new halogen-free flame retardant developed in recent years. It is acidified by concentrated sulfuric acid from natural graphite, then washed, filtered and dried, and then expanded at 900~1000 degrees centigrade. Flame retardant mechanism of expandable graphite is: it is high temperature above 200 degrees at the moment, due to the desorption in the lattice in the compound layer, graphite will be along the axis of the structure showing the expansion of hundreds of times, and reached a maximum volume at 1100 DEG C, 280 times after the final volume of arbitrary expansion can be achieved initially, this feature makes the expandable graphite in fire by volume increase moment the flame goes out. At present, expandable graphite has been commercially applied in different fields, such as polyurethane foam, and also applied to structural combination, cable segmentation and fire prevention of segmented pipelines.
Nitrogen system flame retardant flame retardant is compared with other late development, a small volatile, non-toxic, non halogen, low smoke, no corrosive gas, low price, anti ultraviolet radiation, good compatibility with polymer and the decomposition temperature is high, and many other flame retardants used.
Nitrogen is the most commonly used Flame Retardant Melamine (MA) and its salts (cyanuric acid salt, phosphate, guanidine salt and dicyandiamide), they can be used alone, but also with ammonium polyphosphate and pentaerythritol and other flame retardant composite use. The flame retardant mechanism is: (1) CO2, NH3, N2 heat release and H2O, reduce the concentration of combustible gas generated in the air of oxygen and thermal decomposition of the polymer; (2) non flammable gas generated, took a part of the heat, reducing the temperature of the polymer surface; (3) to generate N2 capture free radicals, inhibition of polymer chain reaction, thereby preventing combustion.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
http://www.yaruichem.com
Flame retardant is a kind of additives that can prevent the polymer material from being ignited or inhibit flame propagation. In early 1950s, with reactive monomer chlorendate developed flame retardant unsaturated polyester, opens up a new way in the field of the research work of flame retardant, then flame retardant containing bromine and phosphorus monomer emerging new.
In 60s, many kinds of flame retardants for PVC plastics were developed. From the early 70s to the middle of 80s, the production and application of PVC flame retardant developed vigorously.
Since 1986, the flame retardant has been carried out and the toxicity of polybrominated diphenyl ether type two environmental problems of flame retardant disputes, promote the new substitute of decabromodiphenyl oxide (including intumescent flame retardant and halogen-free flame retardant) research and development.
However, with the improvement of flame retardant requirements and the enhancement of environmental protection consciousness, the halogen-free, smoke suppression and attenuation of flame retardants have become the frontier topics in the research field of PVC flame retardants at present and in the future. How to develop a new flame retardant with better performance, better effect and more environmental protection? A lot of research work has been carried out in this field at home and abroad. The new flame retardant in twenty-first Century will be halogen free, high efficiency, low smoke, low toxicity, multi-functional composite flame retardant.
At present, the most representative halogen-free inorganic metal compound flame retardants are aluminum hydroxide (ATH) and magnesium hydroxide (MDH). ATH with flame retardant and smoke, filled with three functions, plus it is not volatile, non-toxic, and can produce a synergistic effect with a variety of substances, so its consumption has maintained a high growth rate, which has remained at more than 40% in the proportion of the total amount of flame retardant in. However, ATH usually needs more than 50% to show a good flame retardant effect.
In order to overcome this shortcoming, on the one hand can be used to develop improved granulation technology, ultra fine direction, make size distribution narrowed; on the other hand, the particle surface treatment, silane coupling agent, titanate, paraffin, stearic acid salt and organic silicon to improve its mechanical strength, also can be used to improve coating with a large molecular bonding technology and methods to improve its performance.
Tris(2-chloroisopropyl)Phosphate(TCPP)
Tris(2-chloroisopropyl)Phosphate(Flame retardant TCPP) is a colorless or yellowish oily liquid. It is soluble in benzene, alcohol, carbon tetrachloride and other organic solvents, but insoluble in water and aliphatic hydrocarbons. Its relative density is 1.27-1.31, refractive index is 1.4916 ( 21.5 ), viscosity is 58mm2 / S, chlorine content is 32.8%, and phosphorus content is 9.5%. As the molecule contains phosphorus and chlorine element simultaneously, its flame retardant properties is significant, as well as the plasticization, damp-proof, antistatic effects and so on. Tris(2-chloropropyl) phosphate (TCPP) is an additive flame retardant.
The product is used for the soft / hard polyurethane foam, with thermal and hydrolytic stability good, especially suitable for ASTME84 (Level 11) foam, with low viscosity unsaturated polyester resin in low temperature application and phenolic plastics at. This product is also used to grab the foam sealant and sheet production. For polyvinyl chloride, polystyrene, phenolic resin, acrylic resin and rubber, coating, flame retardant, also used for soft and hard polyurethane foam, epoxy resin, polystyrene, cellulose acetate, ethyl cellulose tree and phenolic plastics, polyvinyl acetate and gun type foam sealant production. Particularly recommended for rigid polyurethane foam has excellent thermal and hydrolytic stability is particularly suitable for ASTM84 (II), compound for polyurethane foam and unsaturated resin and phenolic plastics.
The flame retardant mechanism of ATH is: (1) add ATH to the polymer, reducing the concentration of combustible polymers; (2) to dehydration, heat absorption and inhibition of polymer in 250 degrees Celsius temperature; (3) decomposition of water vapor dilution of the concentration of combustible gas and oxygen, can prevent combustion; (4) in the formation of combustible surface Al2O3, stop burning. MDH is a kind of additive inorganic flame retardant which is developed rapidly. It is low smoke, non-toxic, and can neutralize the acid and corrosive gas in combustion process.
Its flame retardant mechanism is similar to that of ATH. Compared with ATH, MDH high decomposition temperature 100 ~ 150 degrees, can be used for flame retardant finishing temperature higher than 250 DEG C, engineering plastics, and also promote charring effect, but to reach a certain amount of flame retardant effect, in more than 50%, has great influence on the properties of materials. In order to reduce the amount of MDH in the polymer, one method is to make the MDH particles fine, and the other is to modify the surface of MDH by coating technology to improve its compatibility with the polymer.
Expandable graphite is a new halogen-free flame retardant developed in recent years. It is acidified by concentrated sulfuric acid from natural graphite, then washed, filtered and dried, and then expanded at 900~1000 degrees centigrade. Flame retardant mechanism of expandable graphite is: it is high temperature above 200 degrees at the moment, due to the desorption in the lattice in the compound layer, graphite will be along the axis of the structure showing the expansion of hundreds of times, and reached a maximum volume at 1100 DEG C, 280 times after the final volume of arbitrary expansion can be achieved initially, this feature makes the expandable graphite in fire by volume increase moment the flame goes out. At present, expandable graphite has been commercially applied in different fields, such as polyurethane foam, and also applied to structural combination, cable segmentation and fire prevention of segmented pipelines.
Nitrogen system flame retardant flame retardant is compared with other late development, a small volatile, non-toxic, non halogen, low smoke, no corrosive gas, low price, anti ultraviolet radiation, good compatibility with polymer and the decomposition temperature is high, and many other flame retardants used.
Nitrogen is the most commonly used Flame Retardant Melamine (MA) and its salts (cyanuric acid salt, phosphate, guanidine salt and dicyandiamide), they can be used alone, but also with ammonium polyphosphate and pentaerythritol and other flame retardant composite use. The flame retardant mechanism is: (1) CO2, NH3, N2 heat release and H2O, reduce the concentration of combustible gas generated in the air of oxygen and thermal decomposition of the polymer; (2) non flammable gas generated, took a part of the heat, reducing the temperature of the polymer surface; (3) to generate N2 capture free radicals, inhibition of polymer chain reaction, thereby preventing combustion.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
http://www.yaruichem.com
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