Plastic manufacturing process

Crude oil and natural gas are first extracted, and then sent to refineries to extract many substances, including the main components in plastics, that is, ethane is extracted from petroleum, and propane, ethane, and ethane are extracted from natural gas. Propane is sent to a cracking plant to decompose its components. Ethane is used to make ethylene, and propane is used to make propylene. Then a catalyst is added to combine the molecules to form a resin polymer. Because of this structure, plastics are easily shaped under high temperature and pressure.

Polymerization turns ethylene into polyethylene and propylene into polypropylene. These resins are melted and cooled, and then cut into plastic raw material particles. The plastic particles are sent to the factory to be heated to make various plastic products.

Most plastic raw materials are transparent or milky white. Various plastic products require various colors for use or design. This requires dyeing in the plastic processing process; the commonly used dyeing method is in the raw materials before production Mix a certain proportion of color masterbatch or toner, and melt the raw material and color masterbatch or toner in the injection molding machine to produce the desired product color.

Plastic products of various shapes and sizes are used in life. The main production method of these plastic products is injection molding. The three elements required in this process are plastic raw materials, molds, injection molding machines, and the process of injection molding is to put the raw materials Put the raw materials into the hopper of the machine, mix and melt in the injection molding machine, and fill the raw materials into the mold. The raw materials are rapidly cooled and formed in the mold. Finally, the mold is opened to take out the product.

Another common processing method is blow molding. All kinds of plastic bottles, cans, barrels, and the like are blow molded. It is well understood that after the raw materials are melted, they are blown in the mold to form them.

The most intuitive difference between injection molding and blow molding is that the injection molded product is a solid core, and the blow molding is a hollow core.