The Complete Guide To PVC Resins

What is PVC Resin?

PVC is an acronym for Polyvinyl Chloride. Resin is a commonly used material in the manufacture of plastics and rubbers. PVC resin is a white powder used for the production of thermoplastics.

Only PVC resin is a raw material. To convert this resin into the final product, other ingredients must be added. This includes heat stabilizers, plasticizers, lubricants and fillers (definitions given below). When a plasticizer is added, the material becomes softer and more flexible than it would otherwise. It also has better chemical resistance, elasticity and puncture resistance.

Other members of the vinyl family can be used similarly, but PVC is the most popular member of this family. It is considered superior to other alternatives because it can be made into many different shapes and is used in many industries to produce a wide variety of items. 

What Is It Used For?

PVC resin is very popular because it can be manufactured in many different forms to make a wide variety of items in any industry. Common products made from PVC resin include blood bags, windows, pipes, etc.

It is ideal in the construction industry due to its high chemical resistance, water resistance, abrasion resistance, light weight, maintenance free and durability. The additives support the heat resistance of PVC at high temperatures. One of its weaknesses is UV exposure. Additives can help with this, but it is better to avoid prolonged exposure. Therefore, it is often used underground.

One of the most common types of additives mixed with PVC are plasticizers such as butyl glycolate, epoxy resins and dialkyl azelaates.

How is PVC resin made?

PVC resin production typically relies heavily on the use of chlorine and crude oil. There are four PVC manufacturing activities commonly used in its production.

  • The suspension method, 
  • the mass method, 
  • the emulsion/dispersion method, 
  • and the solution method.

Plasticized PVC has many advantages. Because PVC is thermoplastic which means it can be melted and later reformed. PVC is often produced in sheets and which are then reprocessed. These are usually difficult.

PVC resin generally has high chemical resistance. However, it is not visible when the material is exposed to organic chemicals. PVC is also water and abrasion resistant which makes it durable.

Polyvinyl chloride is widely used in two broad categories: rigid and flexible. Each type has its own  advantages and ideal applications in different industries. Flexible PVC works as a wire insulator and as a rubber replacement. Rigid PVC has a variety of uses in construction and plumbing, providing a lightweight, inexpensive and durable material.

Is PVC Toxic? 

PVC releases hydrogen chloride (HCl) gas, which can pose a health risk when burned. Non-PVC electrical cable insulation may be preferred in applications where there is a high risk of fire. Gasses can also be released during material melting (for example, during prototyping and manufacturing processes such as 3D printing, CNC machining, and injection molding). We recommend consulting the Material Safety Data Sheets (MSDS) for various chlorinated hydrocarbon gasses such as chlorobenzene and discussing the manufacturing process with a professional manufacturer.

What are the Benefits of Polyvinyl Chloride?  

PVC offers many key benefits to the industry that have cemented its position as one of the most popular and widely used plastics on the market . 

These benefits are: 

  • Polyvinyl chloride is readily available and is cheaper than expected.
  • Polyvinyl chloride is very dense, which makes it very stiff and  very resistant to impact deformation compared to other plastics.  
  • Polyvinyl chloride has excellent tensile strength.  
  • Polyvinyl chloride is highly resistant to chemicals and alkalis. 

The advantages of PVC have helped cement its position as one of the most widely used plastics in the world. However, although this material is widely used and popular, there are some factors to consider  when using the material.  

 What are the Disadvantages of Polyvinyl Chloride?  

PVC has many advantages that make it a good material to use, but there are some reasons why you should be careful. Disadvantages to consider when using PVC are: 

  • Polyvinyl chloride has very poor thermal stability. For this reason, additives  are usually added to the material during manufacturing to stabilize the material at high temperatures. 
  • Polyvinyl chloride releases toxic fumes when melted or exposed to fire. 

Despite some drawbacks, PVC is a great material overall. A unique blend of properties that are particularly useful in the construction industry. By noting and explaining the shortcomings of the material, you will be able to effectively navigate and compensate for it, allowing you to effectively use the material in future projects.  

Some properties of polyvinyl chloride (PVC) are :

  • Density: PVC is very dense compared to most plastics (specific gravity about 1.4). 
  • Economy: PVC is readily available and inexpensive. 
  • Hardness: Rigid PVC is superior in terms of hardness and durability. 
  • Strength: Rigid PVC has good tensile strength.

Polyvinyl chloride is a “thermoplastic” (rather than “thermoset”) material, which relates to  the way plastics react to heat. Thermoplastic materials become liquid at their melting point (PVC ranges from 100 degrees Celsius to 260 degrees Celsius, depending on  additives).

Some properties and values of PVC

Property                                                          Value

Technical Name                                    –     Polyvinyl Chloride (PVC)

Chemical Formula                                 –      (C2H3Cl)n

Melt Temperature                                  –       212 – 500 °F (100 – 260°C) ***

Heat Deflection Temperature (HDT)     –     92 °C (198 °F) **

Tensile Strength                                    –   Flexible PVC: 6.9 – 25 MPa (1000 – 3625 PSI)

                                                                –  Rigid PVC: 34 – 62 MPa (4930 – 9000 PSI) **

Specific Gravity                                     –     1.35 – 1.45

DEFINITIONS

Plasticizers are organic liquid or solid substances that are incorporated into compatible polymers by melt processing or diffusion to reduce intermolecular interactions and improve molecular mobility.

Heat stabilizers are antioxidants used to reduce the degradation effect of heat generated during processing of biopolymer compositions under harsh conditions (shear, temperature and oxygen).

Lubricants in the form of plastic additives support resin internal lubrication and reduce friction between the polymer melt and the surface. Lubricants prevent the plastic from sticking to the mold surface during processing.

Fillers are particles added to resins or binders (plastics, composites, concrete) to improve certain properties, make the product cheaper, or a mixture of both. The two largest segments of filler material use are elastomers and plastics.

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