What are the processes of plastic processing?
2022-6-28 14:27:49 瀏覽1425次
1. Blister: vacuum forming, called blister, is a plastic processing process. The main principle is to heat and soften the flat plastic hard sheet, use vacuum to adsorb it on the mold surface, and then form it after cooling. It is mainly divided into thick sheet Blister and thin sheet Blister. It is widely used in automobile accessories, lighting, advertising, decoration, large machinery shell, display, air travel, large household appliances, bathroom and other industries.
2. Injection molding: thermoplastic injection molding. This method is to melt the plastic material and then inject it into the membrane cavity. Once the molten plastic enters the mold, it is cooled to form a certain shape according to the mold cavity sample. Common products mainly include: computer case shell, connector, mobile phone shell, keyboard, mouse, audio, etc.
3. Blow molding: also known as hollow blow molding, a rapidly developing plastic processing method. The tubular plastic parison obtained by extrusion or injection molding of thermoplastic resin is placed in the split mold while it is hot (or heated to the softening state). After the mold is closed, compressed air is immediately introduced into the parison to make the plastic parison blow up and cling to the inner wall of the mold. After cooling and demoulding, various hollow products are obtained. The plastic processing technology used for bottles, barrels, cans, boxes and all containers for packaging food, beverages, cosmetics, drugs and daily necessities is blow molding.
4. Extrusion: extrusion is also called extrusion in plastic processing and extrusion in rubber processing. It refers to a processing method in which materials are heated and plasticized while being pushed forward by the screw through the action between the extruder barrel and the screw, and are continuously made into various cross-section products or semi-finished products through the machine head.
1. most plastics have strong corrosion resistance and do not react with acid and alkali.
2. low plastic manufacturing cost.
3. durable, waterproof and light.
4. easy to be molded into different shapes.
5. it is a good insulator.
6. plastics can be used to prepare fuel oil and fuel gas, which can reduce crude oil consumption. 1. when recycling waste plastics, it is very difficult to classify, and it is not economical.
2. plastic is easy to burn, and toxic gas will be produced when burning. For example, toluene is produced when polystyrene is burned. A small amount of this substance will cause blindness and vomiting when inhaled. PVC combustion will also produce toxic hydrogen chloride gas. In addition to combustion, high temperature environment will lead to the decomposition of plastic into toxic components, such as benzene.
3. plastics are made from petroleum refined products, and petroleum resources are limited.
4. plastic will not rot if it is buried underground for hundreds, thousands or even tens of thousands of years.
5. the plastic has poor heat resistance and is easy to age.
6. due to the non natural degradability of plastic, it has become the first enemy of mankind and has also led to the tragedy of many animal deaths. For example, monkeys, pelicans, dolphins and other animals in the zoo will swallow the No. 1 plastic bottle thrown by tourists by mistake, and finally die of pain due to indigestion.
Looking at the beautiful and pure sea, I came closer to see that there were all kinds of plastic garbage that could not be contained by the sea. In the intestines of several dead seabird samples, I found all kinds of plastic that could not be digested.
① Hydrocarbon plastics. It is a non-polar plastic, which can be divided into crystalline and non crystalline. Crystalline hydrocarbon plastics include polyethylene, polypropylene, etc., and non crystalline hydrocarbon plastics include polystyrene, etc.
② Vinyl plastics containing polarity genes. In addition to fluoroplastics, most of them are non crystalline transparent bodies, including polyvinyl chloride, polytetrafluoroethylene, polyvinyl acetate, etc. Most vinyl monomers can be polymerized with free radical catalysts.
③ Thermoplastic engineering plastics. It mainly includes polyformaldehyde, polyamide, polycarbonate, ABS, polyphenylene oxide, polyethylene terephthalate, polysulfone, polyethersulfone, polyimide, polyphenylene sulfide, etc. teflon. Modified polypropylene is also included in this range.
④ Thermoplastic cellulose plastics. It mainly includes cellulose acetate, cellulose acetate butyrate, celluloid, cellophane, etc.
Taizhou Yihao Mold Co., Ltd. is a professional manufacturer of precision molds and precision plastic parts in China. It is mainly engaged in the R & D, design and manufacturing of precision plastic molds, as well as injection molding and component assembly business. It is committed to providing customers with high-quality comprehensive services in mold design, injection molding plastic parts and product assembly.