You must have heard terms like PVC, UPVC, and soft PVC in various industries and even TV commercials, but the question is what is PVC? In this PETROPROVIDERS article, we will refer to different types of PVC grades such as UPVC and soft PVC. In addition, we see the uses of polyvinyl chloride in this article.

What is Polyvinyl Chloride?

Polyvinyl Chloride structure

Polyvinyl Chloride structure

Polyvinyl chloride (PVC) is an economical and widely used thermoplastic polymer. It is widely used in the construction industry for the production of UPVC door and window profiles, pipes (drinking water and sewage), wire and cable insulation, and medical devices.

PVC is the most widely used polymer in the world after polyethylene and polypropylene, but it has a higher price than both. Excessive increases in the price of PVC in recent years have also caused problems for manufacturers and the PVC industry.

PVC polymer is a brittle white solid that is available in powder or granular form. Due to its various features, including lightness, durability, reasonable price, and easy process capability, PVC has now replaced traditional building materials such as wood, metal, concrete, rubber, and ceramics in several applications.

PVC polymer is a linear thermoplastic with a high percentage of amorphous. Usually, the polymerization temperature of PVC is in the range of 45-75 degrees and the PVC produced has a crystallinity percentage of less than 10%. However, by reducing the polymerization temperature, the crystallization percentage of PVC can be increased.

Types of PVC in terms of formulation

Types of PVC pipes

Types of PVC pipes

PVC is widely available in two main categories: UPVC and soft PVC. Specifically, there are the following types for PVC:

Plasticized PVC (PPVC)

The density of these PVCs is about 1.1 to 1.35 grams per cubic centimeter. PPVC polymer is created by adding compatible softeners to PVC, which reduces crystallization. These softeners act like lubricants, resulting in a very clear and flexible plastic known as soft PVC.

Unplasticized PVC (UPVC)

It is a rigid and cost-effective plastic with high resistance to impact, water, air, chemicals, and corrosive environments. This type of PVC is also known as UPVC, PVC-U, or uPVC and does not use softener in its formulation and is known as hard PVC or UPVC.

Chlorinated PVC (CPVC)

By adding chlorine to PVC resin, up to about 56 to 66% is prepared. High chlorine content provides high durability, chemical stability, and flame retardancy. CPVC can withstand a wide range of temperatures. Of course, this grade is not widely used in Iran.

Oriented PVC (OPVC)

By reorganizing the amorphous structure, PVC-U is made into a layer. Biaxial PVC has physical properties (hardness, fatigue resistance, lightness, etc.).

Modified PVC (MPVC)

This type of PVC is formed by adding modifying agents to PVC resin and as a result, will increase its strength.

Benefits of UPVC

  • High strength
  • Flame retardant
  • Suitable for transparent applications
  • Higher chemical resistance than flexible
  • Suitable electrical insulation properties
  • Good vapor barrier
  • Dimensional stability at appropriate room temperature

Disadvantages of PVCs:

  • Hard melting process
  • Poor crack growth resistance
  • Fragility at temperatures below 5 degrees
  • The low temperature of use (about 50 degrees)

Advantages and limitations of soft PVC

Advantages:

  • low price
  • High impact resistance
  • Resistance to acids and oils
  • Suitable electrical insulation properties
  • Flame retardant
  • Easier to process than hard PVC

Disadvantages:

  • Due to the migration of emollients the properties can change over time
  • It is weak against ketones
  • It does not have good strength at high temperatures
  • Not suitable for food contact applications
  • Lower chemical resistance than hard PVC

PVC manufacturing process

Vinyl chloride monomer (VCM) is obtained by the addition and chlorination of ethylene and its pyrolysis. PVC is then made from VCM monomer polymerization.

There are two main methods for producing PVC, suspension and emulsion. In the suspension method, in a pressurized reactor, the monomer is mixed with a polymerization initiator and other additives and suspended in water. Polymerization takes place in the same monomer droplets, and the particle size increases over time as the reaction progresses.

The contents of the reaction reactor are continuously stirred to maintain the suspension and to ensure a uniform particle size of PVC resin. The average particle size is 100 to 150 micrometers. PVCs produced in this way have the ability to absorb a lot of emollients for flexible products.

In the emulsion method, surfactants are used to disperse vinyl chloride monomers in water. The monomer is trapped in surfactant micelles and the polymerizations in the micelles are performed using primers.

Investigate the most important uses of polyvinyl chloride

Huge PVC products

Huge PVC products

Commercially, PVC is one of the most important thermoplastics in the world. In the table and figure below, you can see the types of PVC applications.

Construction

PVC is used to produce door and window profiles, pipes, fittings, valves, waterproof membranes, cable insulation, and roofing.

uses of polyvinyl chloride to make home appliances

Manufacture of curtain rails, drawer walls, cabinets, audio and video equipment frames, flooring, wall coverings, and tablecloths.

uses of polyvinyl chloride for packaging

Making bottles, hard and transparent packaging, cellophane, and adhesive films.

uses of polyvinyl chloride in the automotive industry

Construction of car rear seat, car roof covering, fabric cover, wire insulation, window decoration, and decorative arts.

uses of polyvinyl chloride in the manufacture of drugs

Making tubes and tubes and blood transfusion bags, oxygen tents.

uses of polyvinyl chloride in the electronics industry

Manufacture of protective conductors (electrical pipes), power distribution tanks, battery cases, wire, and cable insulation, and sockets.

Summary of reviews of uses of polyvinyl chloride

Polyvinyl chloride, or PVC, is a widely used plastic. Generally, more than 50% of man-made PVC is used in construction; Because PVC is cheap and has good special properties. In recent years, PVC has replaced traditional building materials such as wood, cement, and pottery in many areas. Despite the emergence of an ideal material in construction, there are still concerns about the cost of PVC for the natural environment and human health.

This polymer is used in various industries and is used to produce a variety of plastics. For example, PVC is used to make auto parts, home appliances, electronics, and durable plastics.

What do you think about the important uses of polyvinyl chloride? Is this substance harmful to human health? Is it cost-effective to use PVC to make plastics? What items do you see in your daily life that are made of PVC?


What are the important applications of polyvinyl chloride?

This polymer is used to produce a variety of plastics, windows, pipes, and medical devices.

Why is the use of PVC not recommended?

PVC contains chemicals such as phthalates and cadmium. These substances are very harmful to children's health.

What does PVC mean?

PVC, means polymer vinyl chloride! This polymer is used in various industries and is composed of vinyl chloride monomers.

Is polyvinyl chloride waterproof?

Yes! Polyvinyl chloride is one of the most important polymers that is water-resistant.