Methods of identifying different plastics 1. Density method: By examining the density of various plastics and using liquid as a medium to see their ups and downs, the category of plastics can be roughly distinguished. Assuming that plastics can float on the surface in water, it can be determined that the raw material is not…
How to identify plastic easily？ First of all, because the darker color pigments are generally very toxic, in general, the darker the color, the more toxic the plastic. Another very important reason for dyeing plastic is that the raw material is waste plastic, in order to cover up the original color. The second is smell.…
Other types of PC are commonly used in: kettles, cups, and bottles. Use: A material that is used in large quantities, especially used in baby bottles, which is controversial because of its content of bisphenol A. Clean measures against bisphenol A The residual bisphenol A in PC, the higher the temperature, the more release and…
PP is commonly used in: soy milk bottles, yogurt bottles, juice drink bottles, microwave lunch boxes. Use: The common melting point is as high as 167 ℃. It is the only plastic box that can be safely placed in the microwave oven and can be reused after careful cleaning. Need special attention, some microwave lunch…
PVC is commonly used in: common raincoats, building materials, plastic films, plastic boxes, etc. It is rarely used for food packaging. Use: This material has excellent plasticity and low price, so it is very popular. It can only heat up to 80 ℃, and it is easy to produce harmful substances at high temperatures, and…
PET is often used in: mineral water bottles, carbonated beverage bottles, etc. Use: heat-resistant to 65°C, cold-resistant to -20°C, only suitable for warm or frozen drinks, high-temperature liquids, or heating, it is easy to deform, and harmful substances to the human body will melt. In addition, scientists discovered that after 10 months of use for…
Plastic processing technology Compression molding Compression molding is also called compression molding or compression molding. Compression molding is mainly used for the molding of thermosetting plastics such as phenolic resin, urea-formaldehyde resin, and unsaturated polyester resin. Calender Calendering is to process the resin and various additives through the gap between two or more calender rolls…
Blow molding Blow molding is also called hollow blow molding or hollow molding. Blow molding is a method in which the hot resin parison closed in the mold is blown into hollow products by the pressure of compressed air. Blow molding includes two methods: blown film and blown hollow products. Blow molding can be used…
Forming definition Plastic molding processing refers to the process of making final plastic products from polymers manufactured by synthetic resin manufacturers. Processing methods (usually referred to as one-time plastic processing) include compression molding (compression molding), extrusion molding (extrusion molding), injection molding (injection molding), blow molding (hollow molding), calendering, etc. Blister After the sheet is heated…
China is a big agricultural country. Agricultural plastic products have become an indispensable material for the development of modern agriculture. It is an irreplaceable technical measure to resist natural disasters and achieve stable, high-yield, high-quality and high-efficiency crops. It has been widely used in China’s agriculture, forestry, animal husbandry, and fishery. , Agriculture has become…
The development of plastic packaging Plastic packaging materials mainly include plastic flexible packaging, woven bags, hollow containers, turnover boxes, etc., which are one of the largest areas in the application of plastic products. Plastic packaging accounts for about 1/3 of the total output of packaging materials, ranking first among all packaging materials. Various mineral products,…
Plastics for the development of machinery The huge plastic market has played a role in promoting the development of the plastic machinery industry. The plastic machinery industry has a wide range of applications including packaging, agriculture, construction, automobiles and other fields. With the continuous development of the domestic petrochemical industry, the plastic machinery industry has…
Application and development of plastics The rapid development of the plastics industry has also brought about a series of social problems caused by waste plastics and waste plastics. The application of plastic products has penetrated into every corner of society, from industrial production to food, clothing, housing and transportation, plastic products are everywhere. Plastics has…
Plastics classification by molding methods According to the different molding methods of various plastics, it can be divided into film pressing, lamination, injection, extrusion, blow molding, casting plastics and reaction injection plastics. 1. Film pressure plastics are mostly plastics whose physical properties and processing properties are similar to those of general solid plastics; 2. Laminated…
Thermosetting plastics refer to plastics that can be cured under heat or other conditions or have insoluble (melting) characteristics, such as phenolic plastics, epoxy plastics, etc. Thermosetting plastics are divided into formaldehyde cross-linked type and other cross-linked types. After thermal processing and molding, an infusible and insoluble cured product is formed, and the resin molecules…
Thermoplastics refers to plastics that melt after heating, can flow to the mold after cooling, and then melt after heating; heating and cooling can be used to produce reversible changes (liquid ←→solid), yes The so-called physical change. General-purpose thermoplastics have continuous use temperatures below 100°C. Polyethylene, polyvinyl chloride, polypropylene, and polystyrene are also called the…
What is special plastic? Special plastics generally refer to plastics with special functions that can be used in special applications such as aviation and aerospace. For example, fluoroplastics and silicones have outstanding high temperature resistance, self-lubricating and other special functions, and reinforced plastics and foamed plastics have special properties such as high strength and high…
What is engineering plastic? Engineering plastics generally refer to plastics that can withstand a certain external force, have good mechanical properties, high and low temperature resistance, and have good dimensional stability. They can be used as engineering structures, such as polyamide and polysulfone. In engineering plastics, it is divided into two categories: general engineering plastics…
Functions of commonly used plastics 1. Polypropylene: Relatively speaking, polypropylene has more varieties, more complex uses, and various fields. The varieties mainly include homopolypropylene (homopp), block copolymer polypropylene (copp) and random copolymer polypropylene (rapp) According to different uses, homopolymerization is mainly used in the fields of wire drawing, fiber, injection, BOPP film, etc., copolymer polypropylene…
Commonly used plastic varieties performance 1. Polyethylene: Commonly used polyethylene can be divided into low-density polyethylene (LDPE), high-density polyethylene (HDPE) and linear low-density polyethylene (LLDPE). Among the three, HDPE has better thermal, electrical and mechanical properties, while LDPE and LLDPE have better flexibility, impact properties, film-forming properties, etc. LDPE and LLDPE are mainly used in…
