polyvinyl chloride
PVC is polyvinyl alcohol in English? The abbreviation of chloride is PVC in Chinese. Using amorphous materials as raw materials, it has ultra-high performance in oxidation resistance, strong acid resistance and reduction resistance. Pvc also has high strength and excellent stability, is not flammable, and can resist the corrosion caused by climate change. This is a good material. Because of its high security, it can be seen everywhere in life.
At the same time, PVC, as a plastic product with huge global output, is divided into soft PVC and hard PVC, which provides different choices for different use occasions. Among them, soft PVC is usually used as the surface material of floor and ceiling, while hard PVC is more used in corrugated board, door and window structure and various chemical manufacturing. Moreover, PVC materials are changeable. By adding different additives, the physical and mechanical properties of PVC can be changed, and it can be used in different occasions. For example, the soft and hard PVC mentioned above can even be made into transparent materials for special needs.
? characteristic
PVC material not only has many advantages such as corrosion resistance, incombustibility, insulation and oxidation resistance, but also keeps a high sales volume in the material market because of its reprocessability and low manufacturing cost. At the same time, it is also because of its wide use and affordable price. A variety of functions have not made it have rising value, but have been occupying a site in the material market at a cheap price. At present, the improvement and design technology of PVC materials in China has reached the international advanced level. From the previous need to import special PVC materials from abroad to the present, we can use our own research and production of PVC instead of imports and start exporting products abroad.
Main danger
Polyvinyl chloride (PVC) is also a common plastic. It is a resin composed of PVC resin, plasticizer and antioxidant, and it is not toxic in itself. However, the main auxiliary materials such as plasticizers and antioxidants are toxic. The plasticizers used in daily-use PVC plastics mainly include dibutyl terephthalate and dioctyl phthalate. These chemicals are toxic, and so is lead stearate, an antioxidant of PVC. When PVC products containing lead salt antioxidants come into contact with solvents such as ethanol and ether, lead will be precipitated. When PVC containing lead salt is used as food packaging, lead molecules will diffuse into oil when encountering fried dough sticks, fried cakes, fried fish, cooked meat products and cakes and snacks, so it is not possible to use PVC plastic bags to pack food, especially oily food. In addition, PVC plastic products will slowly decompose hydrogen chloride gas at high temperature, such as about 50℃, which is harmful to human body, so PVC products are not suitable as food packaging materials.
Medical-grade polyvinyl chloride (PVC) or polycarbonate (PC) are mostly used in disposable medical devices. The thermal decomposition products in the processing of PVC have strong corrosiveness to steel, while PC has high hardness and viscosity, so the parts and components of plasticized parts must have high corrosion resistance, wear resistance and polishing performance. Most medical injection molding machines use hard chromium plated barrel screws or stainless steel as materials to manufacture simple screws that meet the above special requirements. Besides, what if? The gas generated by thermal decomposition during PVC processing needs to be aluminized on the surfaces of moving and fixed templates, aluminized on the surrounding metal plates or made of stainless steel plates. The flat seam of the metal plate is sealed with non-toxic silica gel to prevent the gas generated in the plastic processing from going outside (the gas generated in the plastic processing can be collected by special equipment, purified and released into the atmosphere).
PVC is the main source of dioxins. Dioxin (TCDD) is the most deadly substance in the dioxin family, and it is a well-known carcinogen, hormone decomposer and toxic compound, which is extremely harmful to people and animals. When PVC is produced, recycled and destroyed in an incinerator, or when PVC products are accidentally burned, such as landfill, dioxins will be produced.
In the case of large demand, it is easy to have mixed fish and dragons and uneven quality. Especially when ordinary users buy PVC materials themselves, they are often easily fooled by the black-hearted boss of small shopkeepers. Inferior PVC materials are far inferior to high-quality PVC materials in wear resistance and pollution resistance. Products made of inferior PVC not only have poor functionality, but also have a very short service life. So when you buy PVC materials yourself, please be sure to go to the relevant stores to buy them. The above is about what pvc means, I hope I can help you!