Lamination machine for laminating PVC/HPL/CPL/Aluminum/Paper on MDF/Chipboard
The full name of PVC is Polyvinylchlorid. The main component is polyvinyl chloride. The color is bright, corrosion-resistant, and durable. Due to the addition of plasticizers and anti-aging agents in the manufacturing process, some toxic auxiliary materials are added to enhance its heat resistance and toughness. Extensibility, etc., so its products generally do not store food and medicine. It is a well-loved, popular and widely used synthetic material in the world today. Its global use ranks second among various synthetic materials. According to statistics, in 1995 alone, PVC production in Europe was about 5 million tons, and its consumption was 5.3 million tons. In Germany, the production and consumption of PVC is an average of 1.4 million tons. PVC is being produced and applied worldwide at a rate of 4%. In recent years, the growth of PVC in Southeast Asia has been particularly significant, thanks to the urgent need for infrastructure construction in Southeast Asian countries. Among the materials that can produce three-dimensional surface films, PVC is the most suitable material.
PVC (polyvinyl chloride), the structure of its monomer is simply CH2=CHCl
Chemical and physical properties:
Rigid PVC is one of the most widely used plastic materials. PVC is actually a vinyl polymer material whose material is a non-crystalline material. PVC materials are often added with stabilizers, lubricants, auxiliary processing agents, colorants, impact agents and other additives in actual use. It has non-flammability, high strength, weather resistance and excellent geometric stability. PVC is highly resistant to oxidizing agents, reducing agents and strong acids. However, it can be corroded by concentrated oxidizing acids such as concentrated sulfuric acid, concentrated nitric acid, and is also not suitable for contact with aromatic hydrocarbons or chlorinated hydrocarbons.
The melting temperature of PVC during processing is a very important process parameter. If this parameter is improper, it will cause the problem of material decomposition. The flow characteristics of PVC are rather poor and the process range is narrow. In particular, large molecular weight PVC materials are more difficult to process (this material usually incorporates a lubricant to improve flow characteristics), so small molecular weight PVC materials are commonly used. The shrinkage rate of PVC is quite low, generally 0.2 to 0.6%.
Injection molding process conditions
Drying treatment: Drying is usually not required.
Melting temperature: 185~205°C Mold temperature: 20~50°C
Injection pressure: up to 1500 bar Holding pressure: up to 1000 bar Injection speed: In order to avoid material degradation, a considerable injection speed is generally used.
Runners and gates: All regular gates can be used. If you are working with smaller parts, it is best to use tip-type gates or submerged gates; for thicker parts, it is best to use fan-shaped gates. The minimum diameter of the tip or submerged gate shall be 1 mm; the thickness of the fan gate shall not be less than 1 mm.
Typical use: Polyvinyl chloride is rich in raw materials (petroleum, limestone, coke, salt and natural gas), mature in manufacturing process, low in price and wide in use. It has become the second largest universal in the world after polyethylene resin. Resin, accounting for 29% of the world's total synthetic resin consumption. Polyvinyl chloride is easy to process and can be processed by molding, laminating, injection molding, extrusion molding, calendering, and blow molding. Polyvinyl chloride is mainly used in the production of plastic soft products such as artificial leather, film, wire sheathing, water supply pipes, household pipes, house wall panels, commercial machine casings, electronic product packaging, medical equipment, food packaging, speedboat fenders, Production of plastic hard products such as plates, doors and windows and valves.
PVC can be divided into soft PVC and hard PVC. Hard PVC accounts for about 2/3 of the market, and soft PVC accounts for 1/3. Soft PVC is generally used for the surface of floors, ceilings and leather, but because soft PVC contains softener (this is also the difference between soft PVC and hard PVC), it is easy to become brittle and difficult to store, so its scope of use has been limited. Hard PVC does not contain softener, so it has good flexibility, easy to form, is not brittle, non-toxic and non-polluting, and has a long storage time, so it has great development and application value. Hereinafter referred to as PVC. Soft PVC is mostly used to make vacuum plastic film, which is used for surface packaging of various panels. Therefore, it is also called decorative film and adhesive film. It is used in many industries such as building materials, packaging, medicine and so on. The building materials industry accounts for the largest proportion, at 60%, followed by the packaging industry, as well as several other small-scale applications.
Briefly, an aqueous solution of a salt chemically decomposes at the action of an electric current. This process produces chlorine, caustic soda and hydrogen. Refined, cracked petroleum or gasoline can produce ethylene. When chlorine and ethylene are mixed, dichloroethylene is produced; dichloroethylene can be converted to produce chlorinated vinyl, which is an essential component of polyvinyl chloride. The polymerization process joins the chlorinated vinyl molecules together to form a polyvinyl chloride chain. The polyvinyl chloride produced in this manner was in the form of a white powder. It cannot be used alone, but can be mixed with other ingredients to produce many products.
Vinyl chloride was originally synthesized in the Justus von Liebig laboratory in 1835. Polyvinyl chloride was synthesized by Baumann in 1872. However, it was not until the 1920s that the first commercial products of polyvinyl chloride were produced in the United States, and in the next 20 years, large-scale production began in Europe.
Polyvinyl chloride is flame retardant (flame retardant value is 40 or higher), high chemical resistance (concentrated hydrochloric acid, 90% sulfuric acid, 60% nitric acid and 20% sodium hydroxide), mechanical strength And the advantages of good electrical insulation. However, the heat resistance was poor, the softening point was 80 ° C, and the discoloration began to decompose at 130 ° C, and HCI was precipitated.