In flame retardant polyvinyl chloride and flame retardant polyethylene, antimony trioxide is a very efficient flame retardant because it has a good flame retardant synergistic effect with halogen, which can improve the oxygen index of the material. The self-extinguishing performance of the material.
At present, the arsenic content of high-purity antimony trioxide in China is controlled at ≤300ppm, but there is also a large market for antimony trioxide without repeated purification, because it is cheap! At present, the purity of more than 99.5% of the market is more than 55,000 yuan / ton, and the so-called antimony trioxide has not been purified, the price is only 15,000 yuan / ton, the price difference is nearly four times.
If you add 5% of the formula, only the price of this kind of material will be 2,000 yuan / ton, but this is not a terrible point of cutting corners. The real terrible thing is to be much more serious!
What is arsenic trioxide? The following quoted from wikipedia: "Arsenic trioxide, commonly known as arsenic, molecular formula As2O3, is the most commercially valuable arsenic compound and the main arsenic chemical starting material. It is also one of the oldest poisons, odorless and tasteless, the appearance of white creamy powder It is called arsenic. This is a highly toxic by-product produced by certain specified mineral treatment processes, such as gold mining, high-temperature distillation of arsenopyrite (toxic sand) and condensation of white smoke."
As we all know, arsenic trioxide has long been banned by REACH, but such toxic raw materials are still used by most domestic material manufacturers. Many cable manufacturers do not know the use, the procurement standards do not require environmental protection, in exchange for the damage and hidden dangers of front-line personnel and society.
the so-called low-smoke halogen-free flame retardant material refers to a flame retardant material that does not contain halogen and has a small amount of smoke. Conventional flame retardants include aluminum hydroxide, magnesium hydroxide, and phosphorus-nitrogen flame retardants, and do not contain halogen and other heavy metal salt flame retardants.
However, the quality of materials used in China is uneven. It is not only unable to meet the requirements of physical properties, but even most of the jackets use non-flame-retardant calcium carbonate as a low-smoke halogen-free waste material that is filled or directly recycled.
The optical cable produced by using this material has the characteristics of superior flame retardancy, less smoke during combustion, and no corrosive gas escape, so it is widely used in nuclear power plants, subway stations, telephone exchanges and computer control centers, high-rise buildings, Shopping malls, hotels, radio and television stations, important military facilities, oil platforms, etc., as well as places where people are concentrated and air density is low.
The halogen-free low-smoke, low-halogen and low-smoke characteristics of the optical cable, when the fire occurs, the spread speed is slow, the smoke concentration is low, the visibility is high, and the release amount of harmful gas is small, which is convenient for personnel to evacuate. However, the materials currently used in China are uneven, and it is not only unable to meet the physical requirements, but even most of the jackets use non-flame-retardant calcium carbonate as a filling or direct use to recycle low-smoke halogen-free materials.
It is currently known that optical cable types involving the use of recycled materials and calcium carbonate filling instead of flame retardant sheaths are mainly butterfly optical cables, low voltage cables, video cables, railway signal cables, and the like. Mainly used in places such as rails or indoor buildings. The use of calcium carbonate as a filling sheathing material is not only flame retardant, but also has flammable characteristics, and it is unable to meet the requirements of the flame spread speed and the amount of smoke generated by the combustion. It is entirely for the benefit of reducing costs, regardless of the quality of the project.
The use of recycled plastic as a sheathed optical cable, the service life needs to be evaluated, the biggest hazard is easy aging cracking, can not effectively protect the cable core of the optical cable, so that the service li