I must say that modern life would be very uncomfortable without PVC. What is it for a modern economy? PVC parts today make up to 15 kilograms of the total mass of an average European car, this material is involved in the production of consumer goods (balls, clothes, shoes, furniture, floor coverings, credit cards, etc.)
For more than half a century medicine has also been using PVC. What it is, you can see, referring to the numerous disposable equipment. Here you can find packaging for tablets, tires, surgical gloves, catheters, feeding devices, blood containers. This material is cheap, successfully replaces rubber and glass, is easily sterilized, and can be used inside the human body.
If we look at the things that are in our home, many of them are also made of PVC. What could it be? Polyvinyl chloride often becomes the basis of electrical insulation, pipes, window profiles, children's toys, packaging materials, mobile phones, plastic bottles, tubes for toothpaste and much more.
What determines such a widespread use of PVC? What is it from a chemical point of view? According to its formula (-CH2 – CHCl-) of degree n (degree of polymerization), PVC is a synthetic polymer, which is among the base ones and is produced from chlorine and oil (57 and 43 percent, respectively). Production processes are less than half dependent on the supply of petroleum products, which makes the production of this material profitable and its price low.
Polyvinyl chloride in its appearance is a white powdery substance with good dielectric properties. It is odorless and tasteless, insoluble in water, resistant to oxidation, poorly burned (due to chlorine in the composition), resistant to acids, mineral oils, alkalis, alcohols. When heated to 100 degrees C, the substance decomposes with the release of hydrogen chloride.
PVC production begins with the extraction of chlorine from a solution of sodium chloride (by exposure to an electric discharge). In parallel, ethylene is extracted from the oil (a procedure called “cracking”). After that, chlorine and ethylene are combined to give ethylene dichloride. In turn, vinyl chloride (monomer) is created from dichloride, which is then converted into the desired substance during the polymerization. Various components are added to it, allowing you to get a finished product with certain properties for the industry.
PVC manufacturers use three main methods for the polymerization of monomers: block, suspension and emulsion. In this case, suspensions are used to obtain soft, semi-rigid and hard plastics, and emulsions are used for soft products obtained through plastisols. Depending on the absence or presence of plasticizers, respectively, unplasticized and plasticized material is produced. The first is less resistant to low temperatures (up to minus 15 degrees C), the second withstands cooling to -60 degrees. Today, the most urgent problem associated with these substances is their collection and disposal.