Polyvinyl Chloride

What is Polyvinyl Chloride?

Polyvinyl chloride, more commonly known as PVC, is a durable and versatile material with many applications. PVC is commonly used as an alternative to natural rubber latex because the two materials share so many characteristics and because PVC presents no risk to people with latex allergies or sensitivities. PVC offers excellent stiffness and durability and can be manufactured for many different service environments, such as the thick plastic piping that immediately comes to mind for many people. PVC is often a more cost-effective choice when compared to other materials.

PVC is commonly used to make tubing for medical purposes and other applications. Flexible polyvinyl chloride tubing exhibits great abrasion resistance, flexibility, durability, and stability, along with excellent clarity.

How PVC Is Made

The PVC manufacturing process starts with a short ingredient list: Sea salt and oil. Liquid petroleum is heated and placed under extreme pressure, which triggers a molecular weight change in the petroleum’s chemical components. This weight change is used to identify ethylene within the petroleum so that it can be separated, captured, and cooled to a liquid state.

A similar process is used to extract chlorine from sea salt. A strong current of electricity is sent through a saltwater solution in order to change its molecular structure. As a result, the chlorine can be separated and extracted.

At this stage, ethylene and chlorine are introduced, reacting together to create ethylene dichloride. The ethylene dichloride is placed in a high heat environment with no oxygen, a process called pyrolysis, producing vinyl chloride monomer. Manufacturers may use one of three methods—suspension, emulsion, and bulk—to achieve polymerization, or the linking of the vinyl chloride monomer molecules. The polymerization process results in PVC resin.

Benefits of PVC

Durability.

PVC is extremely resilient to many stressors, including corrosion, chemicals, and weathering, and has excellent tensile strength. These qualities make PVC an especially popular choice for construction and piping. Because PVC holds up well against so many environmental factors, it also lasts longer than other materials in certain contexts.

Excellent flow characteristics.

PVC tubing and pipes have extremely smooth inner linings, which reduces flow resistance and enables pressure maintenance throughout the fluid management system. This is yet another reason why PVC is such a popular choice for piping and plumbing. 

Non-allergenic

PVC doesn’t contain any of the latex proteins found in natural rubber latex. It presents no risk to people with latex allergies or sensitivities. As a result, it’s a very safe option for products that come into contact with the skin, such as medical tubing, catheters, personal protective equipment (PPE), and other products.

Easy to clean and sterilize

PVC is entirely impermeable to germs and is easy to clean and sterilize, all of which are vital in a medical or healthcare setting for infection prevention. Many single-use medical components are made with PVC for this reason. The food and beverage industry also gravitates toward PVC due to its cleanliness and sanitation properties.

Cost-effective

Compared to other materials on the market, PVC is relatively inexpensive, not to mention widely available. In many contexts, choosing PVC allows manufacturers to achieve their original product performance goals while saving money.

Limitations of PVC

The primary drawback of PVC is its poor resistance to heat. If temperatures get too high, the compound begins to break down, and off-gassing may occur. Certain stabilizers can be added during the manufacturing process to improve the heat stability of PVC, but there are some applications, such as hot liquid applications, in which PVC simply may not be the best choice. Additionally, PVC is not compatible with fatty foods.

What is PVC Used For?

Both rigid and flexible PVC are used in many everyday and specialty applications. Rigid PVC is extremely popular in the construction industry because it’s durable and inexpensive. Flexible PVC can be found throughout hospitals and other healthcare settings. Flexible PVC tubing is an excellent material choice for fluid pathway systems and other types of medical and surgical tubing, thanks to its performance characteristics and lack of latex allergens. PVC tubing is also used for laboratory research and development, beverage transfer and dairy processing, distribution and industrial applications, and more.

PVC Products from Kent Elastomer

KEP’s flexible PVC tubing products follow stringent quality standards, making them a top choice in several industries. Choose from a range of PVC compounds for our flexible PVC tubing, including FDA Food Grade compliant, USP Class IV compliant, BPA free, and DEHP and phthalate free compounds choices.

Ready to get started with flexible PVC tubing extruded to your exacting specifications, or want to know if another material would be better suited for your application? Contact our experts today.