Pet molding process can be injection molding, extrusion, blow molding, coating, bonding, machining, electroplating, vacuum metal plating, printing. Here is a brief description of the hot forming process: The thickness of pet is the decisive factor of processing in the process of blistering. When pet is in a relatively stable balance with heating temperature and heating time, a standard blister product can be produced.
Pull the rolled sheet into the oven of the electric furnace and heat it to the softened state. Pull it to the top of the blister mold while it is hot. Move the mold up and vacuumize it to absorb the softened sheet to the surface of the mold. Meanwhile, spray the cooling water on the surface of the formed sheet in the form of mist to harden it. The formed sheet is automatically pulled to the storage box. The pneumatic cutter separates the formed sheet from the unformed sheet, so as to complete the whole process Process.
If the heating temperature is too high and the heating time is too short, the cooling time is too short and the product is easy to deform; if the heating time is too long and the cooling time is too long, the production efficiency is low. Therefore, it is necessary to balance the relationship between material thickness, temperature and time on the premise of ensuring that the product does not deform and the product is in place to maximize productivity
PET structural formula
Pet is a milky white or light yellow highly crystalline polymer with smooth and glossy surface. Creep resistance, fatigue resistance, wear resistance and dimensional stability are good, wear is small and hardness is high, with the largest toughness of thermoplastic: good electrical insulation, little affected by temperature, but poor corona resistance. It is non-toxic, weather resistant, chemical resistant, low water absorption, resistant to weak acid and organic solvent, but not resistant to hot water immersion and alkali.
Advantages of pet as packaging material
1. It has good mechanical properties, impact strength is 3-5 times that of other films, and good bending resistance;2. Resistant to oil, fat, enoic acid, alkali and most solvents;3. It has excellent high and low temperature resistance. It can be used in the temperature range of 120 ℃ for a long time, 150 ℃ for a short time, and – 70 ℃ for a low temperature, and has little effect on its mechanical properties at high and low temperature;4. The permeability of gas and water vapor is low, which has excellent properties of gas resistance, water, oil and peculiar smell;5. High transparency, UV blocking, good luster;6. It is nontoxic, tasteless, hygienic and safe, and can be directly used for food packaging.
Application of PET
Pet is widely used in fiber, film and engineering plastics. PET fiber is mainly used in textile industry. PET film is mainly used for electrical insulation materials, such as capacitor, cable insulation, printed circuit wiring substrate, electrode slot insulation, etc. Another application field of PET film is film base and baseband, such as film film, X-ray film, recording tape, electronic computer tape, etc.; PET film is also made of metallized film by vacuum crossing aluminum, such as gold and silver wire, micro capacitor film, etc. Film sheet can be used for all kinds of food, medicine, non-toxic and sterile packaging materials. Glass fiber reinforced pet is suitable for electronic, electrical and automotive industries. It is used for various coil frames, transformers, TV sets, recording machine parts and casings, automobile lamp holders, lampshades, incandescent lamp holders,relays, rectifiers, etT.
Post time: Feb-12-2020