Classification of uses
Generally refers to the production of large, wide use, good formability, cheap plastic. There are five kinds of general plastics, namely polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS) and acrylonitrile butadiene styrene copolymer (ABS). These five kinds of plastics accounted for the vast majority of plastic raw materials used, the basic can be classified as special plastic varieties, such as: PPS, PPO, PA, PC, POM and so on, they are in daily life in the small amount of the product, mainly used in the field of engineering, National defense science and technology industry and other high-end, such as automotive, aerospace, architecture, communications and other fields. Plastics can be classified into thermoplastics and thermosets according to their plasticity. Usually, thermoplastic plastic products can be recycled, and thermosetting plastics are not, according to the optical properties of plastics to points, can be divided into transparent, translucent and opaque materials, such as PS, PMMA, AS and PC belong to the transparent plastic, and most other plastics are made of opaque plastic.
Properties and uses of common plastics
1. polyethylene: commonly used polyethylene can be divided into low density polyethylene (LDPE), high density polyethylene (HDPE) and linear low density polyethylene (LLDPE). Among the three, HDPE has better thermal properties, electrical properties and mechanical properties, while LDPE and LLDPE have better flexibility, impact properties and film forming properties. LDPE and LLDPE are mainly used for packaging film, agricultural film, plastic modification and so on, while HDPE is widely used in many fields, such as film, pipe, injection of daily necessities and so on.
2.: relatively speaking, polypropylene PP more varieties, use is also more complex, many areas, there are varieties of polypropylene homopolymer (homopp), polypropylene block copolymer (copp) and polypropylene (Rapp), according to different purposes, were mainly used in wire drawing, fiber, injection, BOPP film etc, polypropylene is mainly used in household appliances of injection parts, modified materials, daily injection products, pipes, atactic polypropylene is mainly used for transparent products, high performance and high performance products, pipe etc..
3. PVC: because of its low cost, the product has the characteristics of self ignition, so it is widely used in the field of construction, especially the sewer pipe, plastic steel doors and windows, plates, artificial leather and other uses are the most widely used.
4. polystyrene: as a transparent raw material, in the case of transparent demand, a wide range of uses, such as car shades, daily transparent parts, transparent cups, cans and so on.
5.ABS is a widely used engineering plastics, with outstanding mechanical and thermal properties, are widely used in household appliances, panel, mask, assembly, and other accessories, especially household appliances, such as washing machine, air conditioner, refrigerator, electric fan, the amount is very large, the other in the plastic modification, application it is very wide.
Generally, it can bear a certain external force, has good mechanical properties and high and low temperature resistance, good dimensional stability, can be used as engineering structures of plastics, such as polyamide, polysulfone and so on. In engineering plastics, it can be divided into two categories: general engineering plastics and special engineering plastics. Engineering plastics in mechanical performance, durability, corrosion resistance, heat resistance and other aspects can achieve higher requirements, and processing more convenient and can replace metal materials. Engineering plastics are widely used in electronic, electrical, automotive, building, office equipment, machinery, aerospace and other industries, to plastic instead of steel, plastic instead of wood has become an international trend.
General engineering plastics include: polyamide, POM, polycarbonate, modified polyphenylene oxide, thermoplastic polyester, ultra high molecular weight polyethylene, methyl vinyl polymer, vinyl alcohol copolymer, etc..
Special engineering plastics also have crosslinking type of non crosslinking type. The crosslinking types are poly amino bis maleic amide, poly three triazine, crosslinked polyimide, heat-resistant epoxy resin finger, etc.. Non crosslinked types are polysulfone, polyether sulfone, polyphenylene sulfide, polyimide, PEEK, etc..
Generally refers to the special function, can be used in aviation, aerospace and other special applications of plastics. Such as fluorine plastic and silicone has outstanding resistance to high temperature, self lubrication and other special functions, and enhance the plastic and foam plastic with high strength, high buffer and other special properties, these plastics belong to the category of special plastics.