Plastics (1) General plastics General plastics such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, phenolic plastics and aminoplastics account for more than 75% of the total plastic production.
1) PE。 For example, low-pressure polyethylene (pressure less than 5MPa) is often used to manufacture containers, general mechanical parts, pipes and insulating materials.
2) polypropylene (PP). Strength, hardness, rigidity and heat resistance (no deformation at 150℃) are better than those of low-pressure polyethylene, which is often used to manufacture containers, storage tanks and valves.
3) PVC。 Strength and rigidity are better than polyethylene.
Rigid polyvinyl chloride (PVC) is often used to make structural materials, pipes and electrical insulation materials with chemical corrosion resistance. Flexible PVC is mainly used for casing and sealing of wires and cables.
4) polystyrene (PS). Polystyrene is a kind of material with good rigidity, but it is brittle and hard, and it is mainly used to produce injection molded products.
How many kinds of plastics are there?
ABS (commonly known as engineering plastics) can be used for connectors, chairs and seat boards, and is the main raw material for electroplating (water electroplating) in plastics. PP (common name polypropylene) is used for five-star feet, handrails, foot pads and connectors with low strength requirements. Disadvantages: poor wear resistance and low surface hardness. PVC (commonly known as polyvinyl chloride) is mainly used for edge sealing and insertion conditions. It is suitable for extrusion molding, PVC materials. The temperature stability of processing and molding is poor, especially the color stability is not good. PU: commonly known as polyurethane. Mainly used for handrail (foam) fittings. POM: The common name is Sai Gang. Mainly used for wear-resistant parts such as foot pads, casters, door hinges, hinges and so on. Its performance is resistant to wear and pressure, but its dimensional stability is poor. PA: commonly known as nylon. Mainly used for foot pads, five-star claws, casters and other wear-resistant and long-life requirements. Some models, such as PA66, are resistant to high temperature of 2200, but the disadvantage is that they are easy to change their properties in the sun, easy to break and have poor weather resistance. PMMA: plexiglass (commonly known as sub-afterburner). There are five transparent materials in plastics, and PMMA is one of them, which has the highest transparency. When the workpiece is cut, it smells of acetic acid, and it is easy to deform during processing. It can be shaped and bent by soaking in boiling water. Disadvantages: the surface is easy to scratch, the hardness is low, and the price is more than 20% higher than ABS. PC: commonly known as polycarbonate. This variety is also a transparent material with high surface hardness, scratch resistance, strong impact resistance, high strength and good weather resistance (that is, not afraid of sunlight). The sun board separated by screen in furniture is hollow extruded with this material. Features: high cost, about 40% higher than PMMA.
How many kinds of plastics are there?
According to the different use characteristics of well-known plastics,
Plastics are usually divided into three types: general plastics, engineering plastics and special plastics.
① General plastics generally refer to plastics with large output, wide use, good formability and low price. There are five kinds of general plastics, namely polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS) and acrylonitrile butadiene styrene (ABS). They are all thermoplastic.
② Engineering plastics generally refer to plastics that can bear certain external forces, have good mechanical properties, high and low temperature resistance and good dimensional stability, and can be used as engineering structures, such as polyamide and polysulfone. engineering plastics
Among engineering plastics, it can be divided into general engineering plastics and special engineering plastics.
③ Special plastics generally refer to plastics with special functions, which can be used in special application fields such as aviation and aerospace. For example, fluoroplastics and silicone resins have outstanding special functions such as high temperature resistance and self-lubrication, while reinforced plastics and foamed plastics have special properties such as high strength and high cushioning. These plastics belong to the category of special plastics.
What are the classifications of plastics?
Classification of plastics There is no accurate classification of plastics at present. Roughly classified as follows: 1. According to the physical and chemical properties of plastics, thermoplastics: plastics that can be softened by repeated heating and hardened by cooling within a specific temperature range, such as polyethylene plastics and polyvinyl chloride plastics. Thermosetting plastics: plastics that can be solidified into insoluble substances due to heating or other conditions, such as phenolic plastics and epoxy plastics. According to the use of plastics, general plastics: generally refers to plastics with large output, wide use, good formability and low price. Polypropylene, polyvinyl chloride, etc. Engineering plastics: generally, it refers to plastics that can bear certain external forces, have good mechanical properties and dimensional stability, and can still maintain their excellent properties at high and low temperatures, and can be used as engineering structural parts, such as ABS, nylon, alum, etc. Special plastics: generally refers to plastics with special functions (such as heat resistance and self-lubrication). Suitable for plastics with special requirements, such as fluoroplastics and silicone resin. According to plastic molding methods, molding plastics are classified into resin mixtures for molding, such as general thermosetting plastics. Laminated plastics refers to the fiber fabric impregnated with resin, which is integrated into a whole material through superposition and hot pressing. Injection molding, extrusion and blow molding of plastics:-Usually refers to melting and flowing at barrel temperature. A resin mixture that hardens rapidly in a mold, such as ordinary thermoplastics. Casting plastic: liquid resin mixture, which can be injected into the mold without pressure or with a little pressure, and can be hardened into a certain shape product, such as MC nylon. Reaction injection molding plastics: generally speaking, liquid raw materials are injected into the mold cavity under pressure to make them react and solidify to make finished products, such as polyurethane. Plastic powder is divided into plastic semi-finished products and finished products, also known as plastic powder. It is mainly made of thermosetting resin (such as phenolic resin) and filler through full mixing, pressing and crushing. Such as phenolic plastic powder. Reinforced plastic: a kind of plastic with reinforced materials, some mechanical properties of which are greatly improved compared with the original resin. Foam: Plastic with many micropores on the whole. Film: generally refers to flat soft plastic products with a thickness less than 0.25mm.. ..
Types and uses of plastics
Properties and uses of common plastics 1. Polyethylene: Commonly used polyethylene can be divided into low pressure polyethylene (HDPE), high pressure polyethylene (LDPE) and linear high pressure polyethylene (LLDPE). Among them, HDPE has good thermal, electrical and mechanical properties. However, LDPE and LLDPE have good flexibility, impact properties and film forming properties. LDPE and LLDPE are mainly used in packaging film, agricultural film and plastic modification. And HDPE has a wide range of applications, such as films, pipes, daily necessities for injection, etc. 2. Polypropylene: Relatively speaking, polypropylene has more varieties, more complex uses and more fields. The main variety is homopolymer polypropylene. Block * * * polypropylene (copp) and random * * * polypropylene (rapp) are mainly used in stretching, fiber, injection molding, BOPP film and other fields. According to different uses, * * * polypropylene is mainly used for injection-molded parts of household appliances, modified raw materials, daily injection-molded products, pipes and so on. Random polypropylene is mainly used for transparent products, high performance products and high performance. Products have the characteristics of self-flame-retardant, so they are widely used in the construction field, especially in sewer pipes, plastic steel doors and windows, plates, artificial leather and so on. 4. As a transparent raw material, polystyrene is widely used, such as car lampshades, daily transparent parts, transparent cups and cans. 5.ABS is a widely used engineering plastic with excellent physical, mechanical and thermal properties. Widely used in household appliances, panels, masks, components, accessories and so on. Especially household appliances, such as washing machines, air conditioners, refrigerators, electric fans, etc. In addition, it is also widely used in plastic modification.
How many kinds of plastics are there? Is plastic a kind?
Commonly used plastics are: ① polyvinyl chloride (PVC), which is the most used plastic in buildings. The density of rigid PVC is 1.38~ 1.43g/cm3, with high mechanical strength and good chemical stability, and the service temperature range is generally between-15~+55℃. Suitable for manufacturing plastic doors and windows, sewer pipes, trunking, etc. ② Polyethylene (PE) polyethylene plastic is mainly used for water supply and drainage pipes and sanitary wares in buildings. ③ Polypropylene (PP) has the lowest density among all plastics. About 0.90. Polypropylene is usually used to produce pipes, sanitary wares and other building products. ④ Polystyrene (PS) is a colorless and transparent glassy plastic. Polystyrene is mainly used to produce foam insulation materials, light-transmitting materials and other products in buildings. ⑤ABS plastic ABS plastic is a kind of modified polystyrene plastic, which consists of acrylic acid (a), butadiene (b) and styrene (s). You can make ABS plastic.
What are the classifications of plastics? -What are thermoplastics? -What is thermosetting plastic?
There are many kinds of plastics, because different monomers and their compositions can synthesize different plastics. Thermosetting plastics and thermoplastics are a classification of plastics. The former can't be reused, while the latter can be produced repeatedly. In simple and popular terms, thermosetting plastics are the raw materials that eventually form products (materials and shapes) during heating, and once the materials are formed, they cannot be changed. Thermoplastics can be softened or melted by heating after the material is formed. It is processed and shaped in a softened or melted state, and the shape is fixed after cooling. It can be reshaped by reheating. English abbreviation for common plastics, commonly known as purpose PE, polyethylene, PP, polypropylene 100-fold adhesive. Plastic microwave lunch box HDPE high-density polyethylene hard soft rubber cleaning products, bath products LDPE low-density polyethylene cling film, plastic film and other LLDPE linear low-density polyethylene PVC vinyl chloride vinyl chloride vinyl chloride vinyl chloride vinyl chloride is rarely used in food packaging GPPS universal polystyrene hard rubber EPS foamed polystyrene foam rubber HIPS impact-resistant polystyrene hard rubber AS, SAN styrene-acrylonitrile transparent strong adhesive ABS acrylonitrile-butadiene-styrene super unbreakable adhesive PMMA polymethacrylate, plexiglass EVA ethylene-vinyl acetate polymer rubber PET polyester mineral water bottle, carbonated beverage bottle PBT polybutylene terephthalate PA polyamide nylon POM POM resin Saigang, Duogang PPO PPO Noryl PPS polyphenylene sulfide PU polyurethane PS bowl instant noodles box, snack box.