The hottest nano functional plastic and its applic

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Nano functional plastics and their applications in household appliances

modern plastic processing applications nano functional plastics and their applications in household appliances Shi Jinsong (Taixing nano materials Co., Ltd., Chinese Academy of Sciences, 225401) application. The achievements of nano materials, the main component of the external insulation system that withstands the cold and heat cycle, and their influence and penetration in various fields are very eye-catching. Laurel, the Nobel Prize winner, once said that countries that valued micron technology in the 1970s have become developed countries. Now countries that value nanotechnology must be tempered by this process to become an advanced country in the 21st century. Nano materials have achieved satisfactory application results in many fields, such as building materials, environmental protection, semiconductors, chemical fibers, cosmetics, machining and so on. Nowadays, the application of nano materials in the plastic industry also has a promising prospect, and plastic is one of the important materials of household appliances. Household appliances often use some plastics with special functions, such as antibacterial plastics, flame retardant plastics, conductive plastics, magnetic plastics, toughened and reinforced plastics, and biodegradable plastics to meet the requirements of environmental protection. 1 Types and characteristics of nano functional plastics in order to meet the needs of some special industries and some special parts, with the emergence of nanotechnology, there have been many special functional plastics modified by nano materials. 1.1 antibacterial plastics antibacterial plastics are achieved by adding antibacterial agents to plastics. Using nanotechnology to add a small amount of nano inorganic antibacterial agents to plastics can produce high-efficiency antibacterial plastics. Inorganic antibacterial agents are contact sterilization. Due to the reduction of particle size, the number of inorganic antibacterial agents per unit weight increases and the specific surface area increases, so the contact area with bacteria is increased and the antibacterial effect is improved. At the same time, due to the ultra-fine particle size of antibacterial agents, they can penetrate the cell wall of bacteria (E. coli is about 600mn) into the cell body by Coulomb gravity, destroy the activity of cell synthase, and the cell loses the ability of division and reproduction and dies. Therefore, functional nano inorganic antibacterial plastics have extremely excellent properties: high safety, non-toxic side effects; Long antibacterial effect and good slow-release effect; The antibacterial efficiency is very high, and the antibacterial rate against Escherichia coli is more than 99%; The broad antibacterial spectrum overcomes the singularity of general antibacterial materials; Good stability, with light stability and thermal stability that ordinary silver antibacterial agents cannot compare. Toughened and reinforced plastics are filled with inorganic fillers with nano particle size in plastics, commonly used are montmorillonite, SI2, Ti2, etc. due to the poor compatibility between inorganic nanoparticles and plastics such as polypropylene, it is difficult to match. At present, the more mature technology is to fill plastics with nano-sized ultrafine CaC03 after surface treatment Nano CaCO3 has obvious heterogeneous nucleation effect on the crystallization of PP and other plastics. Proper addition can increase the tensile yield strength and bending modulus of polypropylene and other plastics. It can be seen that it touches the fields of diplomacy, economy and trade, transit transportation, mining, infrastructure construction, finance, culture, housing construction, etc. nano material filling can achieve the purpose of toughening and greatly improve the comprehensive mechanical properties of plastics. 1.3 flame retardant plastics can be made into high-efficiency flame retardants by surface modification with nano sb23 as the carrier, and its oxygen index is several times that of ordinary flame retardants. Because the particle size of nano materials is ultra-fine, its activity is great after surface treatment, its thermal decomposition speed is greatly accelerated during combustion, the heat absorption capacity is enhanced, and the surface temperature of materials is reduced. In addition, ultra-fine nano material particles can cover the surface of ABS condensed phase, which can well promote the formation of carbonization layer and form a non combustible barrier between combustion source and substrate, thus playing the role of isolation and flame retardance. In addition, nano sb23 has a good match with ABS and other plastics, and has the advantages of good thermal stability, non-toxic, durable flame retardant and so on. Major in chemistry, has been engaged in the research, preparation and application of nano materials, and has published several articles on modern plastic processing and application. 1.4 conductive plastics commonly used conductive plastics are prepared by adding copper powder, silver powder or carbon black. Due to the poor dispersion of ordinary carbon black and other materials in plastics and poor compatibility with plastics, their application is limited. Nano conductive powder with excellent performance can be prepared by coating a layer of dense SN2 and sb23 films on tiz with nano titanium dioxide as the carrier. Because the particle size of the conductive powder is ultra-fine, according to the theory of atomic diffusion behavior, the lattice vibration speed of its nanoparticles is accelerated, so it has good compatibility with plastics and good whiteness, which widens the field of the application of conductive powder in plastics. 1.5 magnetic plastic magnetic plastic is commonly known as plastic magnet. Due to the surface effect, nano magnetic materials will have a significant lattice contraction effect, which will reduce the lattice constant, causing the deformation and elongation of nano particles in the tensile experiment. It is not only the change of surface atom transport and configuration within the marking line, but also the change of surface electron spin conformation and electron energy spectrum. Its magnetic domain is small, showing a single domain structure. Due to the volume effect, its magnetic properties have changed dramatically. The magnetic interaction of nanocrystals is not only limited to a single grain, but also can extend across the interface, so that hundreds of grains are magnetized and arranged. With the reduction of particle size, its coercivity can be significantly enhanced, and the magnetic properties have been significantly improved. Plastics with good magnetic properties can be made by mixing super magnetic materials such as nano ferrite and rare earth with plastics. 2 Application of nano functional plastics in household appliances the material renewal of household appliances has completed the process of plastic replacing metal, and now the process of replacing ordinary plastics with nano functional plastics has begun. The application of functional plastic materials has promoted the development of household appliance industry. On the other hand, the development of household appliance industry has also put forward many new topics for plastic materials and their processing technology, and nano functional plastics came into being in this case. High efficiency nano antibacterial plastics are mainly used for door handles, door linings, drawers, etc. of refrigerators, as well as antibacterial stainless steel cylinders, antibacterial washing pumps, antibacterial wave wheels and other components of washing machines. In addition, they are also widely used in air conditioners, water heaters, mineralized kettles, microwave ovens, electric cookers and so on. Toughened and reinforced plastics are mainly used for the sealing strip of refrigerator door, the inner cylinder of washing machine and the shell and base of various household appliances. Flame retardant plastics are widely used in household appliances, such as electric irons, microwave ovens, rice cookers, televisions, various lighting appliances and plugs and sockets of all electrical appliances. Conductive plastic is mainly used for the shell of household appliances to shield or reflect the electromagnetic wave harmful to human body generated by household appliances, and for dust removal of air conditioners. Magnetic plastics have developed rapidly, accounting for 15% of the total consumption of magnets. A large number of them are used for rotor and stator parts of micro precision motors, refrigerator door sealing magnetic strips, televisions, tape recorders, video recorders, loudspeakers and other parts of household appliances. Conclusion various nano functional plastics have broad application prospects in household appliances. Therefore, we should strengthen the development of various functional plastics, follow the international development trend in terms of new materials with purpose and requirements, strive to improve the competitive advantage of future products in the application of functional plastics, and make contributions to the application of nano functional plastics in household appliances

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