Cable Jacket Material Comparison and Insulation Guide

With so many cable types available, choosing the right one isn’t always straightforward. Even after narrowing your needs down by function, you’re still left with dozens of material options for insulation and jacketing.

Depending on the environment, your project might need protection from corrosion, abrasion, moisture, or extreme temperatures. You also have to weigh cost and supplier availability on top of that.

A quick cable jacket material comparison before ordering helps set your industrial assembly up with the right type of protection.

Jacketing or Insulation? Understanding the Role of Each

Cable jacketing is the outer layer that protects all other components from moisture, chemical, and mechanical hazards. Jackets’ side jobs include adding flexibility for installation and color-coding for easy identification.

Cable insulation is the non-conductive covering attached to bare wires to separate conductors from each other, both physically and electrically. It not only protects against current leakage; it also offers a second layer to fight heat and moisture. 

A cable’s insulation material type can influence the overall electrical properties of the cable. For example, an insulation’s thickness determines voltage rating, and its ability to withstand high temperatures means it can carry more current without failing. 

Jacketing and insulation share many materials, most of them derivatives of rubber or plastic. However, not all insulation materials can be used for jacketing.

What to Look For in Cable Insulation & Jacketing Materials

There are three main branches of cable jacket and insulation material: thermoplastic, thermoset, and fluoropolymer. (We’ll discuss them further below.) Each has its own family of materials, and manufacturers offer product variations on each material.

It’s a lot to take in. Above all else, watch for these traits that may influence performance in your application.

• Flexibility – This helps with ease of installation in a rigid environment. It’s also important in dynamic applications (i.e. a robotic arm), as an inflexible cable would degrade quickly and limit nozzle movement. Rigid cables, however, may be more durable than flexible ones.
  
  
• Environmental durability – Many industrial cable applications require the ability to withstand some combination of moisture, chemicals, oil, fire, and UV light.
  
  
• Thermal properties – Cable materials have varying performance in both hot and cold. You don’t want your cabling to melt or become brittle in extreme conditions.
  
  
• Stripability – Some materials are easier than others to remove. Consider this trait if you might later need to terminate or slice a cable.
  
  

Thermoset Options for Cable Protection

Thermoset materials consist of basic polymers that are cured or vulcanized to form a cross-linked structure. Once a thermoset has been cured, you can’t remold it, which makes it a more heat-resistant jacketing material in high-load and short-circuit situations. 

This quality makes thermoset cables the popular choice for circuits prone to a conductor overload.

Other benefits include:

• Burns to an ash with no drip when exposed to flame
• Extra-resistant to damage during challenging installations
• Longer service life in harsh applications
• Oil- and chemical-resistant

Thermoset jacketing and insulation is common in:

• Heat treating
• Glass and ceramic kilns
• Foundries
• Aluminum processing
  
  

Common Thermoset Materials for Cable Protection

Thermoplastic Options for Cable Protection

Thermoplastics is a branch that includes a few well-known options: PVC and polyurethane cable jackets.

A thermoplastic is a material that changes hardness during heating and cooling. In extreme-temperature applications, this could mean the cable becomes deformed, decreasing its physical properties.

On the plus side, these cheaper materials are often easier to strip, which makes large-volume application more efficient (i.e. for automation equipment).

Other benefits:

• More economical for low-intensity use
• Lightweight
• Great colorability for easy-to-ID cables in low lighting
• Better electrical properties

Thermoplastic jacketing and insulation is common in:

• Medical applications
• Food & beverage industry
• Military purposes
• Industrial power plants
• Interior spaces either beneath raised floors or above dropped ceilings
• Marine and low-temperature environments
• Power & control cable applications
• CPE cable insulation displays
  
  

Common Thermoplastic Materials for Cable Protection

Fluoropolymer Options for Cable Protection

This family of plastic resins is known for its toughness. For example, fluoropolymer insulation boasts high resistance to acids, solvents, and bases that corrode cables.

Other benefits include:

• Miniaturized design with high dielectric strength, allowing for thinner walls
• Steady electrical performance, even with thin walls
• Difficult to crush or cut

Fluoropolymer jacketing and insulation is common in:

• Military
• Aerospace
• Electronics
• Automotive
• Appliances
• Automation
• Critical building construction
• Confined areas (i.e. tunnels, transit, & submarines)
  
  

Common Fluoropolymer Materials for Cable Protection

Other Cable Jacketing and Insulation Options

Performance-minded engineers usually stick with thermoset cables in applications where failure isn’t an option. Some of the most extreme environments may require a unique fluoropolymer material.

That said, there are other, less-common materials under all three main branches. Basically, there’s a solution for any industrial application you could dream up.

Not every cable and wire manufacturer offers all of these materials. However, manufacturers who also offer distribution services can source the cable types they don’t make in-house. 

Need Help Sourcing the Right Cable Materials?

Start with our free electronic component guide to make safe choices about jacketing, insulation, and sourcing.

This article was originally published in May 2023 and was recently updated to reflect current industry trends.