How many kinds of plastic materials are there?
The molecular structure of thermosetting plastics is the body structure, softening also occurs in heated, can plastic into a certain shape, but is heated to a certain extent or amount of curing agent, hardened stereotypes, re heating will not soften and change the shape of the. Thermosetting plastic processing, molding, the heat is no longer softening, and therefore can not be recycled, such as phenolic plastics, amino plastics, epoxy resin, etc. belong to this kind of plastic. Thermosetting plastic forming process is more complex, so continuous production has some difficulties, but its good heat resistance, not easy to deformation, and the price is relatively low.
There are many kinds of plastics. So far, there are about more than 300 kinds of plastic produced in the world. Many classification methods of plastic, there are two kinds of commonly used: 1, according to the nature of the heated plastic divided into thermoplastic and thermoset plastic molecular structure are linear structure, softening or melting when heated, plastic into certain shape, after cooling and harden. After heating to a certain extent, it softens again and hardens again after cooling. This process can be repeated many times. Such as PVC, polyethylene, polystyrene and so on. Thermoplastic molding process is relatively simple, can be continuous production, and has a high mechanical strength, so the development of very fast.
Plastic classification, composition and characteristics, plastic is a widely used synthetic polymer materials, in our daily life, plastic products abound. We wake up from the use of toiletries, the breakfast dishes, to work with the rest of the stationery, with cushions, mattresses, and TV, washing machine, computer shell, and night gave us the light of the lamps in various shapes...... Plastics have gradually replaced many materials and utensils that have been used for decades and centuries with their excellent performance, becoming an indispensable assistant in people's life. Plastic, metal in hard wood, light transparent glass ceramics, corrosion resistance, rubber elasticity and toughness in a body, in addition to daily necessities, plastic more widely used in aerospace, medical equipment, petroleum chemical industry, machinery manufacturing, defense, construction and other industries.
According to the different uses of plastics is divided into general and engineering plastics in general plastic refers to the yield, low price and wide application range of plastics, mainly including polyolefin, PVC, polystyrene, phenolic and aminoplastic five varieties. Many of the products used in everyday life are made from these general plastics. Engineering plastics are plastics that can be used as engineering structural materials and instead of metals to make machine parts and components. Such as polyamide, polycarbonate, POM, ABS resin, PTFE, polyester, polysulfone, polyimide and so on. Engineering plastics has the characteristics of low density, high chemical stability, good mechanical properties, excellent electrical insulation, easy processing, widely used in automobiles, electrical appliances, chemical industry, machinery, instruments, and other industries, is also used in space navigation, missiles, etc..
