Low smoke halogen-free granulator
Low smoke halogen-free cable material granulator
Low smoke halogen-free flame retardant polyolefin cable material is usually made of polyolefin blend resin plus flame retardant filler aluminum hydroxide, It is composed of magnesium hydroxide and some antioxidants added to improve the heat resistance life. Sometimes in order to reduce the amount of smoke produced when burning, some smoke inhibitors are added, such as vanadium, nickel, molybdenum, iron, silicon, and nitrogen compounds. Its flame retardant mechanism is: when burning, the flame retardant fillers aluminum hydroxide and magnesium hydroxide will release crystal water and absorb a large amount of heat. At the same time, the dehydration reaction will generate a large amount of water vapor, which can dilute the flammable gas and prevent it from burning. Burning will also form a layer of non-melting and non-combustible oxide hard shell on the surface of the material, blocking the channel for the polymer to react with external hot oxygen, making the material ultimately flame retardant and self-extinguishing.
Low-smoke halogen-free flame-retardant polyolefin cable materials must have good flame retardancy. The aluminum hydroxide and magnesium hydroxide in the formula must have a large filling amount, usually more than 100%, and an internal mixer is required. After better compatibility between the materials and inorganic substances, single-screw cooling and granulation equipment is used to make materials, disperse the output, and achieve energy consumption, low-smoke halogen-free cable material granulator: liter density mixer, cone double feeder- Single screw - hydraulic automatic screen changer, air-cooled grinding surface and hot cutting - first cyclone separator, second cyclone separator - extended air-cooled vibrating screen silo. Welcome to consult: Research on halogen flame retardant
Table 3 High expansion and low expansion The effect of expanded graphite on the limiting oxygen index
The content of expanded graphite can be seen from Table 3. As the amount of expanded graphite increases, the oxygen index of 3 continuously increases.
3 can make pure from. Rising to . is more effective than The function of isolating oxygen expandable graphite is a physical mechanism, mainly the dense carbon layer forming a physical isolation layer, protecting the polymer under the carbon layer, and isolating heat and mass transfer. .The latest research methods of halogen-free flame-retardant polyolefin materials
In recent years, with the advent of cone calorimeters, the application and evaluation of flame-retardant materials have also been carried out in depth. Cone calorimeter was proposed by the National Institute of Science and Technology in 2001. It is a new generation of polymer combustion measuring instrument based on oxygen consumption. Compared with traditional laboratory evaluation methods such as oxygen index, cone calorimeter There is a good correlation between the instrument and the results of large-scale combustion experiments. It can simultaneously give the heat release rate (R), total released heat, effective combustion heat, extinction area during ignition, soot yield, mass loss rate (R), etc. Combining it with R can study whether the flame retardant is a gas phase mechanism or a condensed phase mechanism for polymer flame retardancy. Combining infrared spectroscopy, photoelectron spectroscopy and thermogravimetric analysis can further explore the combination of flame retardants and polyolefins and the chemical phenomena of the material combustion process, thereby analyzing the flame retardant mechanism and providing theory for the next step in the development of new flame retardant systems. in accordance with. France B systematically studied the influence of the chemical structure and characteristics of the carbonized layer on the flame retardant effect [3]. A few papers have studied the influence of carbon layer strength on the flame retardant effect. The development prospects of halogen-free flame retardant polyolefins can be seen from Table 3. As the amount of expanded graphite increases, the oxygen index of 3 can make pure It is more effective to rise from Effectively isolate oxygen. The function of expandable graphite is a physical mechanism, mainly the dense carbon layer forming a physical isolation layer, protecting the polymer under the carbon layer, and isolating heat and mass transfer. .The latest research methods of halogen-free flame-retardant polyolefin materials. In recent years, with the advent of cone calorimeters, the application and evaluation of flame-retardant materials have also been carried out in depth. Cone calorimeter was proposed by the National Institute of Science and Technology in 2001. It is a new generation of polymer combustion measuring instrument based on oxygen consumption. Compared with traditional laboratory evaluation methods such as oxygen index, cone calorimeter There is a good correlation between the instrument and the results of large-scale combustion experiments. At the same time, the heat release rate (R), total released heat, effective combustion heat, ignition time, extinction area, soot yield, mass loss rate (R), etc. are given. Combining it with R can study whether the flame retardant is a gas phase mechanism or a condensed phase mechanism for polymer flame retardancy. Combining infrared spectroscopy, photoelectron spectroscopy and thermogravimetric analysis can further explore the combination of flame retardants and polyolefins and the chemical phenomena of the material combustion process, thereby analyzing the flame retardant mechanism and providing theory for the next step in the development of new flame retardant systems. in accordance with. France B systematically studied the influence of the chemical structure and characteristics of the carbonized layer on the flame retardant effect [3]. A few papers have studied the impact of carbon layer strength on the flame retardant effect. Before the development of halogen-free flame-retardant polyolefins, it can be seen from Table 3 that with the increase in the amount of expanded graphite, the oxygen index of 3 can make pure from . rises to . is more effective than of combustible gases enter the combustion zone and isolate oxygen more effectively.
The function of expandable graphite is a physical mechanism, mainly the dense carbon layer forming a physical isolation layer, protecting the polymer under the carbon layer
and isolating heat and mass transfer.
Low smoke halogen-free cable material granulator