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Anonymous users2024-02-08I think that the raw materials should be selected according to the requirements of the parts, and the quality of the plastic should be determined according to the plastic products! Doesn't seem to make sense:
Because there are many factors that affect the quality of plastic products in the forming process!
1.Determine the properties of plastic parts according to the physical properties of plastic raw materials! 2.Some raw materials have their own fireproof properties, but the addition of toner, mold release, etc. will affect their properties!
3. There are many conditions in the process of beer and plastic that also affect the quality of its parts, some materials need to be soaked, some need to be heated, etc.! 4, Part design, mold design!
Beer and plastic machine control!
1. Look at the brightness of the surface and whether it is transparent.
2. Look at the whiteness, not only on the surface, but mainly on the whiteness of the section, and the whiteness determines everything.
3. Look at the hardness, bite it with your teeth to know that the good materials are hard, and if they are too soft, they are not pure.
4. To see whether it is sinking, it is to look at the amount of stone powder, and there will be more or less stone powder in the general recycled material, because the raw materials of the recycled material are not very pure, and if you do not add additional stone powder, it will generally not sink.
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Anonymous users2024-02-071. Good processing characteristics.
Plastics can be processed into a variety of shapes according to the use requirements, and the processing technology is simple, which is suitable for mechanized large-scale production.
2. Light weight. The density of plastic is in between, generally only 1 3-1 4 of steel, 1 2 of aluminum, 1 3 of concrete, and similar to wood. It is used for decoration and decoration projects, which can reduce the construction intensity and reduce the weight of the building.
3. High specific strength.
The specific strength of plastic is much higher than that of cement concrete, close to or even more than steel, and it is a lightweight and high-strength material.
4. The thermal conductivity is small.
The thermal conductivity of plastics is small, about 1 500-1 600 of metals. The thermal conductivity of foam plastic is only about 1 1500 for metal, 1 40 for cement concrete, and 1 20 for ordinary clay bricks, which is an ideal thermal insulation material.
5. Good chemical stability.
Plastics have good corrosion resistance to general acids, alkalis, salts and greases, and are much better than metal materials and some inorganic materials. It is especially suitable for doors, windows, floors, walls, etc. of chemical plants.
6. Good electrical insulation.
Generally, plastics are poor conductors of electricity, and their electrical insulation is comparable to that of ceramics and rubber.
7. Good performance design.
By changing the formula and processing technology, it can be made into engineering materials with various special properties. Such as high-strength carbon fiber composite materials, sound insulation, thermal insulation composite panels, sealing materials, waterproof materials, etc.
8. Decorative.
Plastic can be made into transparent products, can also be made into a variety of color products, and the color is beautiful, durable, but also can be made with advanced printing, embossing, electroplating and bronzing technology with a variety of patterns, patterns and surface three-dimensional, metallic products.
9. It is conducive to the industrialization of construction.
Many construction plastic products or accessories can be produced in factories and then assembled on-site, which can greatly improve the efficiency of construction.
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Anonymous users2024-02-06The main thing that comes to mind is the environment.
The biggest disadvantage is that it is difficult to degrade. Once used, most of them cannot be used, and even after burial, it will take tens or even millions of years to degrade naturally. Although some degradable plastics have been developed, it is difficult to say whether they will pose other problems (the molecules of plastics themselves are almost non-existent in nature).
You can search for "white pollution", there is a whole lot of information.
The second is a large amount of pollution generated during production, such as sewage.
Third, in addition to thermoplastic materials, most of them cannot be changed after molding (such as many plastic bags). So if you can't, it will cause waste.
Fourth, the possible disadvantage is that plastic may not be a sustainable material because it is extracted from petroleum and other raw materials.
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