Views: 7 Author: China xicheng Publish Time: 2021-06-02 Origin: China xicheng
How is PVC sheet made
The chemical method of making PVC sheets involves the use of the simplest units, called monomers, which are linked together during the polymerization process to form long molecular chains (also called polymers), called polymers.
This is the case with polyvinyl chloride, which is made from vinyl chloride monomer, usually through the polymerization of its original vinyl chloride monomer. Some monomers exist in the form of reactive gaseous chemicals, some of which may cause health hazards when in direct contact with humans. In this case, they are produced and processed under strict control to protect health, safety and the environment.
On the other hand, polyvinyl chloride and other polymers are polymerized from monomers, which are solid, chemically stable, and do not affect human health. Vinyl chloride is the raw material of polyvinyl chloride, which is a gas at ambient temperature, but is usually stored in liquid form under pressure. Ethylene and chlorine are raw materials for polyvinyl chloride.
The basic petrochemical industry produces ethylene and propylene through the pyrolysis of naphtha or natural gas. Naphtha is mainly supplied by the refining industry that uses crude oil as a raw material. The chlor-alkali industry uses industrial-grade salt as the main raw material to produce caustic soda, chlorine and hydrogen through electrolysis.
In the first stage of the PVC production process, ethylene and chlorine are mixed to produce an intermediate product called ethylene dichloride; then it is converted into vinyl chloride, which is the basic component of polyvinyl chloride or PVC. The polymerization process links vinyl chloride molecules together to form polyvinyl chloride chains. The PVC produced by this method is a white powder. This is not used alone, but mixed with other ingredients to provide various product formulations.
Most commercial plastics are mainly composed of carbon and hydrogen. The difference between polyvinyl chloride is that it contains chlorine (approximately 57% by weight), carbon and hydrogen. The presence of chlorine in the molecule makes PVC particularly versatile because it is compatible with various other materials. The chlorine content also helps make PVC flame retardant. It can also be used as a "sign" for distinguishing PVC in the automatic sorting system for plastic recycling. Polyvinyl chloride formulations can be formed through various technologies and can be made into the final product form with very little energy. PVC polymer is chemically stable, neutral and non-toxic. Polyvinyl chloride formulations have a wide range of applications, including the most sensitive applications, such as medical equipment, as well as construction, automobiles, and cables.
Characteristics and color of PVC sheet
Features: high surface hardness, good scratch resistance; surface resistance value of 6 ~ 10 8 ohm 10, with excellent antistatic function, outstanding impact resistance and chemical solvent resistance; beautiful appearance, very smooth and smooth; light transmittance Above 73%.
The flame retardant grade is ul-94:v-0.
Color: transparent, smoky, milky white, gray, etc.
What are the quality grades of PVC boards
Divided into four quality levels:
1. Grade A PVC board (ivory white, gray), density 1.5, brand new material, low filling.
2. Class B PVC board (ivory white, gray), density 1.6. New materials and fillers.
3. PVC white board (steel window white board), recycling white board.
5. Grade C PVC board (grey, black), recycling grade.
The thickness range is 1-25 mm. The width is 1300MM, 1000MM, 1500MM, and the length is determined.