All cables need insulation. Most cables do have polyethylene or PVC as their insulation layer. However, it does not works well in a harsh environment. Another alternative is available in the market, called the PTFE or TFE wires. What is it, and how does it apply to different industries? Let’s look into it.
Table of Contents
- What is Tetrafluoroethylene (TFE)?
- How to make PTFE Coatings?
- PTFE Application
- Which Hook-up wire use PTFE/TFE?
- Which Coaxial Cables use PTFE/TFE?
What is Tetrafluoroethylene (TFE)?
TFE or Tetrafluoroethylene is a gas having no specific color or odor. Manufacturers use the TFE to create fluoropolymer resins like PTFE or polytetrafluoroethylene in industries.
Fluoropolymer resins have a wide range of uses in the industry. However, these polymers are highly flammable, even if oxygen is not present. Thus, their chemical instability makes them difficult to handle as they will explosively decompose in the environment leading to industrial accidents.
Caption: PTFE Shielded Twisted Pair Cable
How to make PTFE Coatings?
Du Pont chemist Roy Plunkett discovered polytetrafluoroethylene (PTFE) unintentionally in 1938. At first, planned to generate a new refrigerant (TFE) by treating hydrochloric acid with Tetrafluoroethylene, so he used metal cans to store the TFE gas.
However, on April 6, 1938, Plunkett observed some weight in a bottle, but it had no gas. Due to his curiosity, he began cutting the metal can open to discover the cause of added weight. Finally, he saw a white, flaky powder inside the pressure bottle.
The TFE polymerized overnight, causing the production of that white powder. Moreover, to speed up the process, the iron can act as a catalyst to speed up the process. Later on, people registered the white polymer as Teflon®.
Four elements are important to make Teflon® or PTFE: hydrofluoric acid, fluorspar, chloroform, and water in a chemical chamber. Next, you will heat it at high temperatures such as 1094 to 1652 degrees F (590 to 900 degrees C). There are two basic steps in the production of PTFE,
- Hydrofluoric acid, chloroform (tri-chloromethane), and fluorspar join to make the chemical compound known as TFE through pyrolysis. Moreover, TFE is extremely flammable, making it a dangerous substance to carry. Thus, you need to make the finished product (PTFE) at the same location where you synthesize the TFE.
- Then, using tiny amounts of catalysts like ammonium persulfate or succinic acid peroxide, you will develop the TFE by radical polymerization. Additionally, the process also relies heavily on water.
Caption: Teflon Thermal Covers
Fluorinated thermoplastics are unique because you can use them in situations that require high heat, high purity, chemical inertness, low temperature, nonstick, and self-lubrication properties. Thus, PTFE is common in the chemical, automotive, industrial, medical, electrical, and electronics industries.
Polyethylene is common in low-end electrical parts but not in high-end parts. On the other side, PTFF, which has good dielectric properties and a high melting point, is perfect for high-end uses. Moreover, it gives a good performance as an alternative to polyethylene.
According to the industries, the PTFE is applicable in
- Automotive Industry: O-rings, Gaskets, shaft seals, valve stem seals, power steering transmission, fuel hose linings, etc.
- Chemical Industry: Impeller, Pumps, Tanks, Diaphragms, heat exchangers coating, autoclaves, reaction vessels, containers, etc.
- Medical Industry: heart patches, ligament replacements, cardiovascular grafts, etc.
- Electrical and Electronics Industry: Electrical insulation, Flexible Printed circuit boards, semiconductor parts, hook-up wires, coaxial cables, etc.
- Industrial Application: Non-stick surfaces, gears, bearings, valves, pumps, fittings, seats and plugs, slide plates, etc.
Caption: PFTE Tape for adhesive backing
Which Hook-up wire use PTFE/TFE?
PTFE hook-up and lead wires operate in harsh conditions. These wires, such as MIL-W-16878/4 or MIL-W-16878/5, can endure high temperatures, frequencies, and other hindrances. Moreover, these PTFE can withstand the toughest weather condition and is abrasion-resistant wire.
These hook-up wires are reliable and resist stress, chemical, and UV radiations, and mold growth. Additionally, it is biocompatible and non-toxic to the environment. Thus, while saving space and weight, it is also friendly to the surroundings.
MIL-W-16878/4 is a hook-up wire made to meet military standards in harsh environments. The wire’s conductors are plated, and the insulation is made of polytetrafluoroethylene (PTFE). You can use it with up to 600 volts and 200 degrees Celsius. It conforms to the HP3 Type E standard of the National Electrical Manufacturers Association (NEMA).
This MIL-Spec wire is very resistant to oil, grease, oil, solvents, fungus, and chemicals, and you can put it in gasoline vapor, liquids, and oils without worrying about it getting damaged. The smooth surface of the PTFE insulation makes it easy to handle and protects against ozone and erosions.
MIL-W-16878/5 wire is a hook-up wire used by the military to wire electrical and electronic equipment from the inside. The wire is insulated with rough polytetrafluoroethylene (PTFE), which has great thermal properties and can be used in temperatures from -60°C to 200°C. Additionally, this wire is very resistant to oils, gasoline, chemicals, fluids, and the effects of time and weather. The American Wire Gauge (AWG) sizes range from 32 to 4. Moreover, a dual UL 1180 rating for wires from 32 to 10 AWG.
M16878/6-Type ET Wire is also a military spec wire used in military equipment as a low-voltage lead wire. The wire is insulated with a PTFE, which can be used in a wide range of temperatures, from 200°C to -60°C. Because the wire is thin, flexible, and has a low-friction coating, you can use it in tight places. Also, the wire is resistant to chemicals, oil, fuels, and water very well.
Which Coaxial Cables use PTFE/TFE?
Many coaxial cables use PTFE as a dielectric or insulation jacket. Some PTFE coaxial Cables are
- RG142 Coax
- RG178 Cable
- RG179 Cable
- RG180 Cable
- RG188 Cable
- RG316 Cable
- RG400 Cable
PTFE Conductor Insulation is a tetrafluoroethylene polymer used to produce different parts in many industries. The usage of PTFE ensures the components and wires are durable for a long time. Moreover, The Wire & Cable can withstand high temperatures and chemical decompositions. Here at Bloom, we offer wiring harnesses and cable assemblies with many options available.