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The United States has developed ultra-thin carbon nanotubes, foam products can be reduced in flammability, Sanmei has developed ultra-thin carbon nanotubes, foam products can be reduced in flammability, and Sanmei has developed ultra-thin carbon nanotubes

According to a report by the physicist organization network on January 16, by adopting a unique sandwich structure at the nanometer scale, scientists at the National Institute of Standards and Technology (NIST) have developed a multi-walled carbon nanotube material that can greatly Reduce the flammability of foam products. Researchers said that the new technology is expected to reduce fires caused by soft decoration by a third. Related papers were published in the professional journal "Solid Film". This new technology, invented by the National Institute of Standards and Technology, combines multi-walled carbon nanotubes with two polymer materials like a sandwich, and superimposes this three-layer material into four consecutive layers. This kind of nanomaterial, which sounds quite "thick", can actually be described as "thin as a cicada wing"—its overall thickness is less than one-hundredth of the diameter of a human hair. In the early stages of the research, the material scientists Jin Yanxi (transliteration) and Rick Davis, who were in charge of the project, set three key goals for the new material: full coverage of the porous surface of the foam material, uniform distribution of nanotubes, and simple and easy-to-promote manufacturing methods. For this reason, they tested a variety of materials, hoping to improve the fire resistance and delay the spread of flame, but the performance was not ideal. In the test, they chose carbon nanotubes, but this material, which is made of carbon atoms like a cylindrical wire mesh, cannot be firmly attached to the surface of the foam. To solve this problem, they chose medical carbon nanotubes, which are often used to increase the viscosity of DNA molecules in cell culture. It is characterized by a layer of amino groups containing nitrogen molecules on the outside. This choice proved to be correct. Medical carbon nanotubes can be evenly distributed among the flame-retardant materials and firmly "grasp" the surface of the material in contact with it. In addition, this material makes full use of the rapid heat dissipation capability of carbon nanotubes. In addition, even if it encounters high temperatures, the carbon nanotubes in the coating are completely scorched, the scorched layer also has a stable flame-retardant structure, which can form a carbon protective layer to prevent the flame from continuing to spread. Davis said that compared with the brominated flame retardants that are currently commonly used in soft decoration, the new technology has better flame retardant effects. Compared with the untreated foam products covering the carbon nanotube flame retardant material, the flammability is reduced by 35%. If it can be widely promoted, the new technology is expected to reduce fires caused by soft decoration by one third. Whether in public places such as offices and hotels, or in our homes, foam decorations are used more and more frequently, and in many cases it is the culprit that caused the spread of fires. Statistics show that there are 6,700 fires caused by soft decoration in the United States each year, and 480 people are killed. In fact, people's current criticism of brominated flame retardants is not the flame retardant effect, but its toxicity. The new study points out that it has a complete victory in flame retardancy, but it does not explain the toxicity problem. If in this respect, it will undoubtedly become a fire protection "protective umbrella" for many beautiful buildings in the future. Of course, the application of flame retardants is far more than construction, national defense, military, aerospace... its stage is everywhere