What is PTFE Material – The Ultimate Guide

PTFE is a versatile fluoropolymer which can be found used in various industries due to its high performing nature. It is a combination of fluorine and carbon atoms.

Some other names of this material:

1. Teflon
2. Polytetrafluoroethylene

Key Elements in Polytetrafluoroethylene

Polytetrafluoroethylene is made of unique major elements. Below are some details:

Molecular or Chemical Structure of PTFE.

Teflon’s molecular structure [CF₂-CF₂]n can be compared to that of PE or polyethylene. The major difference in the two has to do with all hydrogen atoms being replaced with fluorine.

Bond

Teflon molecules consist of C-F and C-C bonds. These binding energies are respectively 4.6-5.0 and 3.3 eV. Other elements of Teflon include water, hydrofluoric acid, chloroform, and fluorspar.

More resources:

• PTFE – Source: Wikipedia
• Polytetrafluoroethylene – Source: Science Direct

PTFE History

Roy J. Plunkett in the year 1938 by chance discovered Teflon. This happened when he tried to make new refrigerant related gases. Plunkett measured the bottle to be sure of the gas amount it consumed.

However, his interest peaked in the origin of the weight. So, he chopped the bottle into two.

He saw a white substance what was waxy in the bottle that was quite slippery too. With further analysis done, he got to know that it was polymerized perfluoroethylene.

In the year 1941, the material was patented by Kinetic Chemicals. They patented it as a new type of fluorinated plastic. Then, it was later in the year 1945 registered as the Teflon trademark.

Since Marc Gregoire, a French engineer, was already using this material on his fishing equipment, he decided to try it on his wife’s (Colette Gregoire) cooking utensils. This was in the year 1954. Marc then developed the very first PTFE-coated, nonstick cookware under the Tefal trade name.

It was until the year 1961 in the United States of America that Marion A. Trozzolo the very first non-stick cookware. Since 1961, non-stick pans have become very famous worldwide. Now, they can be found in millions of homes with different brand names.

Advantages of Polytetrafluoroethylene

There are many reasons why you should consider Teflon for your applications:

 

• Highly chemical resistance
• Good dielectric properties.
• A wide temperature of -400°F to 400°F.
• It is non-stick.
• It has low friction co-efficient
• Good electrical insulator or insulation features.
• Meets food grade compliance.
• Highly resistant to wear.
• Is able to resist weathering.
• Has no issues of ageing or embrittling
• Good corrosion protection characteristics.
• High flame resisting features.
• Good thermal stability features.

Limitations of PTFE

Conventional Polytetrafluoroethylene comes with some limitations where its use is concerned. Knowing these limitations will help you know how to the material.

Some of them include:

• Given that PTFE is naturally is non-stick, it is quite difficult to bond.
• It is corrosive and highly prone to fumes that are toxic.
• Abrasion and creep sensitivity.
• It has low radiation resistance.

PTFE Material Properties

At the moment, Teflon is one of the few engineering material with superior mechanical, physical and chemical properties.

So, even as you choose PTFE material, it is important to consider the following:

Mechanical Properties

• 50 MPa Tensile Modulus
• 300% – 550% Elongation at Break
• Co-efficient of friction 0.300
• 0 max Hardness Rockwell R
• 2 MPa Flexural Yield Strength

Physical Properties

• It is naturally a soft material.
• Fillers can be added to ensure its hardness is increased.
• Teflon that is unfilled doesn’t absorb water. However, when filled, it is able to absorb some little moisture amount. 0.100% water absorption percentage.
• Teflon comes with a density within the 2.1 to 2.3 g/cm³
• Melt velocity within 1 to 10 GPa every second.
• 18 Dynes/g of Surface Energy

Chemical Properties

• Good chemically inert features.
• It has good temperature resisting features.
• Good heat resisting abilities.

Thermal Properties

• Teflon has an elevated thermal stability beneath 440°C which comes with no clear degradation.
• Melting Temp from 317 – 337°C
• Its melting point stands at 327°C.

Electrical Properties

• Ideal for electrical insulation purposes.
• Dielectric strength -19.7 KV/mm
• Its dielectric constant is 2.0

More resources:

• PTFE Properties – Source: HANSA
• PTFE Temperature Range – Source: HANSA

PTFE Manufacturing Process

 

The process of manufacturing Teflon is very simple when the right information is obtained. Below is a step by step guide on this process:

Step 1 – Acquire Raw Materials

For PTFE manufacturing to commence or start, you will need fluorspar, water, chloroform, and hydrofluoric acid.

Step 2 – Heating Raw Material

Bring all raw materials together and heat beneath higher temperatures pyrolysis. The end result is mostly in a gaseous form, and is then transformed into liquid. This happens under very high pressure within temperatures that are low.

Step 3 – Fill the Reaction Chamber

Fill reaction chambers with clean water and initiator chemicals. Add the liquid obtained from heating raw material into the chamber as well. Immediately liquid Teflon meets the initiator, polymerization begins, and solid grains form. These grains stay on the water surface.

Step 4 – Water Draining

With the ideal Teflon weight is achieved, the polymerization process will stop on its own. When it halts, water draining from the reaction chamber begins.

Step 5 – Drying and Pulverizing Teflon

The rest of the Teflon grains are made dry and then pulverized using a mill.

Step 7 – PTFE formed

To achieve perfect drying, an oven can be used. Over 360°C heating is required to ensure that Teflon is made into unique shapes. Using an oven is the best to get perfect drying results. During this time, it becomes like a gel and you get Teflon.

More resources:

• Manufacturing PTFE – Source: HANSA
• How is Teflon Made – Source: HPM

PTFE Machining and Fabrication

There are so many ways of transforming PTFE materials into useful products. The best part is that, machining PTFE is very easy.

For instance, some machining and fabrication forms include:

Cutting PTFE – punching, die cutting, drilling, etc.

Joining PTFE – welding PTFE material, use fasteners, bending, etc.

Forming process – compression molding PTFE is a popular way of making many parts.

Remember, injection molding PTFE is virtually impossible. This is because it will hardly flow above the melting. Therefore, it will require special processing technique.

In additional to these, CNC machining PTFE is a popular processing technique. You can make many custom PTFE parts. Among the key processes in CNC machining are:

• CNC milling PTFE
• CNC turning PTFE
• CNC drilling PTFE

Again, even as you machine PFTE, you must pay attention to the following key variables:

• Achieving tight tolerances can be cumbersome due to the stress creep. Another variable that may make this hard to achieve is the high coefficient of expansion.
• The soft nature increases possibility of tool chatter.
• Extreme pressure may cause PTFE part deformation
• High heat generated during machining process makes it difficult to make unbalanced sections

Generally, a cemented carbide tool is suitable for PTFE machining.

More Resources:

• Compression Molding PTFE – Source: PTi
• Machining Teflon – Source: WayKen

Improved or Reinforced PTFE

Reinforced Teflon is important because it helps in forming barrier films. These barrier films makes it difficult for materials to stick to coated fabrics. It comes with very stable properties of durability and is affordable too.

Reasons why Fillers are Added to PTFE

• Fillers help in enhancing the temperature properties of PTFE.
• Its chemical properties will be based on the filler type being used.
• PTFE porosity (electrical properties) is enhanced with these additives.
• It improves creep resistance.

Different Grades / Filler Types of PTFE

In reinforcing Teflon, the use of glass fibers is very famous. Apart from glass fibers used in reinforcing PTFE, there are the different grades of Teflon with Virgin PTFE standing tall.

Impact that the Different Fillers Have on PTFE Material

Virgin PTFE

This grade type is one that comes without fillers. So, it is Teflon with no fillers. Some of its unique properties include:

• Highly safe and hygienic.
• Its chemical resistance is good.
• Comes with the best electrical properties.
• Good flexural characteristics.
• Has exceptional thermal stability.

Some of its unique applications are gaskets, contact & medicine, food, bellows, human consumption uses, etc.

Glass Fiber Filled PTFE

When glass is added to PTFE, it becomes more durable and stronger. It also reduces its flexibility and its tendencies to creep. Some unique properties it has include:

• Has very high compressive strength.
• Good chemical resistance.
• Enhanced resistance to wear under load.
• This type of PTFE is highly abrasive than virgin PTFE is.

Some applications under this grade include bridge bearing pads, pipe supporting pads, ball valve parts, etc.

Carbon Filled PTFE

Carbon when added to PTFE improves its compressive strength. This makes PTFE highly resistant to wear. It also reduces deformation.

• Has very high compressive strength.
• Has high chemical resistance levels.

Some of its applications are air compressor rider and piston rings.

Graphite Filled PTFE

When added to PTFE, Graphite provides very similar benefits as carbon does. However, graphite filled teflon will not have the high level of wear resistance.

• Enhanced resistance of friction.
• Better electrical conductivity.

Can be used as shafts, bearings, etc.

Bronze Filled PTFE

The addition of bronze to Teflon brings these benefits:

• Enhanced resistant to wear
• Better heat conductivity is generated.
• It becomes more pressure resistant.
• It is able to resist creep more.
• Good thermal conductivity.

Some common applications of this type of PTFE include bushings, bearings, piston rings, etc.

Stainless Steel Filled Teflon

When Stainless Steel is added to PTFE, it enhances its features in the following ways:

• High resistance to wear
• Has better chemical resistance compared to bronze filled types.

They are used in making parts or components used in steam environments.

Calcium Filler Teflon

Calcium fluoride is best to be added to Teflon when its application will require coming into contact with chemicals like strong alkalis and hydrofluoric acid. They are mostly used for electronic or electrical applications, automotive applications, etc.

MoS₂ Filled Teflon

This filler is used to enhance Teflon’s anti-friction properties since it comes with a lubricating effect. It is also used with bronze and glass. Other fillers that you will find added to PTFE include polyimide, Mica, Alumina, etc.

Forms PTFE Material Exist

You can get PTFE material in many forms and configurations depending on your unique requirements and specifications.

PTFE Sheets

 

These sheets come in different sizes. So, based on your needs, you can choose from sizes 8mm to 50 mm in thickness. They are flat in look and thin. However, their width can also be worked on based on your needs.

PTFE Rods

These rods are round and long. They come in different sizes. This means, you will need to buy based on your needs. You will find them ranging from 4mm to 120mm diameter in thickness. Also, the lengths can differ.

PTFE Powder

Teflon powder mostly comes in different colors with white being the most dominant. It is sold in unique packages with different quantities.

PTFE Dispersions

Teflon dispersions are designed to release coatings and for media impregnation. They are mostly made to come in the form of liquid.

PTFE Fabric/PTFE Packing

 

PTFE fabrics are mostly designed to come in different thickness levels, with or without self-adhesive backs, brittle or smooth surfaces, different colors, etc.

They are braided from PTFE filament forming strong and durable sealants.

Comparing PTFE with Other Materials

PFA Material vs PTFE

Properties	PFA	PTFE
Synthetic Names	Perfluoroalkoxy	Polytetrafluoroethylene
Brand Names	Teflon PFA	Teflon
Melting Point	575 – 590 °F / 300 – 310°C	327°C
Tensile Strength	4060 – 4500 psi	1,500 – 3000 psi
Weathering Resistance	Excellent	Excellent
Applications	Not used more in the cookware industry in the area of coating. Some applications include heat exchangers, medical PFA tubing, drum liners, etc.	Very famous in the cookware industry due to its use in coating cooking pots or pans, etc. Other applications include seals, pump parts, etc.
Structure	Two carbon atoms bonded as one through oxygen atoms, with all carbon atoms completely fluorinated.	Only fluorine and carbon atoms

 

ETFE vs PTFE Material

Properties	ETFE	PTFE
Synthetic Names	Ethylenetetrafluoroethylene	Polytetrafluoroethylene
Structure	Made from fluorine, carbon, and hydrogen.	Made from fluorine and carbon atoms.
Applications	Used more in constructing frame structures.	Used for cable and 5G applications.
Melting Point	225 – 270 °C	327°C
Tensile Strength	5500 – 7000 psi	1,500 – 3000 psi

 

FEP vs PTFE Material

Properties	FEP	PTFE
Synthetic Name	Fluorinated ethylene propylene copolymer	Polytetrafluoroethylene
Melting Point	Quite high	Quite low (about 40° lower)
Dissipation Factors	Over 6 times higher compared to PTFE	Quite low
Flexibility	Quite flexible	Quite low in flexibility
Applications	Some coating applications that have to do with detergent exposure, etc.	Ideal in the production or making of pipes and containers., etc.

 

PTFE Material Grades

Apart from filling PTFE, the material exist in different grades depending on specific user requirements. You may choose:

Food Grade PTFE Material

PTFE material is FDA food grade complaint or approved. So, it can be used in coating cooking utensils, food processing, and more. Its low coefficient of friction makes it perfect for other applications such as bushing, bearing, etc.

Mechanical Grade PTFE Material

It is true that this material doesn’t have properties that can overtake virgin PTFE. However, it has a coefficient of friction that is quite low. This makes it ideal for high-performance components, mechanical parts, etc.

PTFE Coating Material

Teflon coating materials easily withstand harsh chemicals and high temperature conditions. Its industrial coatings come with very high temperatures for operating (260°C) and also a very low coefficient of friction.

PTFE Composite Material

Some of its properties you need to note are below:

• Chemically resistant.
• Self-lubricating.
• Absorbs moisture.
• Thermal stability.
• High mechanical strength.
• Resists contamination.
• Electrical insulation

Expanded PTFE Gasket Material

Expanded PTFE material has unique properties that make it a perfect choice for many applications requirements.

Some unique features include:

• ePTFE gasket material is very soft and flexible compared to PTFE sheet gaskets. So, it easily conforms to rough and irregular surfaces.
• This material is easy to compress. Due to that, creep and cold flow is easily reduced.
• You can find expanded PTFE also on rolls as Joint Sealants.
• Good chemical resistance.
• Is able to work to temperatures +260°C.
• Is not corrosive, wetting, and is odorless.

Use of Polytetrafluoroethylene Material

PTFE Insulation

Used here to make insulator cables, wires, etc. This is due to its properties of being able to withstand the highest temperature levels, good dielectric strength, and also resist chemicals.

PTFE Gasket

These gaskets when used provides good thermal insulation and are able to resist corrosive or harmful chemicals. They are used in equipment that handle chemicals as well as petrochemicals.

PTFE Pipes and Fittings

These are ideal for manufacturing compressor rings, bushings, and more. This is because they are chemically inert, stable, have high dielectric strength, have the ideal temperature range of up to +260°C.

PTFE Bearings

Bearings come in different types like slide bearings, sleeve bearings, ball bearing, bearing pad, linear bearing, thrust bearing, etc. These bearings are used more in applications that have high loads, and limited speeds. The good thing about these bearings has to do with their no maintenance characteristics.

PTFE Seals

These are mainly sealants. Some applications that require the use of these seals are compressors, mechanical seals, oilfield equipment, brake systems, aircraft engines, etc. There is the shaft seal, seal ring, oil seal, seal tape, etc.

PTFE Cookware

Non-stick cookware like saucepans, frying pans, and others are mostly coated with PTFE. This is done to prevent the food being cooked from sticking inside the pan. It also helps to make food preparation very easy. It is FDA approved and safe.

PTFE Lubricant

It is a unique film lubricant used like grease or oils are used to reduce friction between two surfaces. They are used to coat items like cookware too and used for lubricating locks, hinges, slides, etc. It is also known as PTFE lube.

PTFE Valves

Due to the good properties of PTFE, its use in making industrial valves is famous. It is able to withstand corrosive chemicals and is chemically inert. You will find in the market chemical check valves, ball valves, valve seats,  control valves, diaphragm valves, PTFE-lined butterfly valves, etc.

PTFE Machine Parts

These parts are mostly used for industrial purposes. They mostly come with different components used to achieve specific needs in the world of manufacturing. Some of these parts include valves, valve seats, dippers, valve body, bushings, etc.

PTFE Guide Ring

This component is designed to ensure metal to metal contact between cylinders and piston do not happen throughout the sliding process. They are very easy to put together and resistant to wear.

PTFE O-ring

When PTFE is used in O-rings, they showcase some very exceptional features like being able to resist all chemicals and fluids up to +260°C. These components are used mostly in the pharmaceutical, chemical, and medical engineering industries.

Other related product include PTFE washer,

PTFE Bushings

These bushings are used in various applications like shaft bearings, valve seats, pump housings, gaskets, etc. They are perfect for applications in the chemical industry and other industries where the best corrosion resisting features are needed.

PTFE PCB Material

PCB materials made with PTFE coatings or materials are very common where PCB laminate materials are concerned. This is due to its ability to offer constant dielectric properties. It is also known as the PTFE printed circuit board.

PTFE Roofing Material

Also known as PTFE-coated membrane, this material is a woven fiberglass membrane with high level of durability, resistant to weather, and very sustainable for roofing purposes.

PTFE Tape Material

This tape is unique and versatile. It is used to seal gas, water, and air to ensure they do not leak through their threaded connections. This is needed more on lines with high level of pressure. There are some types of PTFE tapes designed to meet specific needs as well.

Different Industries using PTFE Material

Different industries around the world make use of PTFE materials in their different forms to achieve the best results in their various production works. Some industries where PTFE applications thrive include:

• Computer industry – used to make game mice.
• Aerospace industry – ideal for gears, bushings, seals, etc.
• Industrial industry – found in outdoor garments, gaskets, lubricants.
• Cookware industry – used in coating non-stick pots and pans.
• Clothing industry – Used for making clothing.
• Medical industry – For making urine collection equipment or devices, filtration membrane to deliver drugs, pipes, tees, spacers, etc.
• Safety Industry – used for firefighting gear.
• Consumer items industry – Guitar strings.
• Construction industry – insulators, electrical installation, slide beatings, load bearings, etc.
• Chemical industry – vales, pipes, hoses, o-rings, etc.

Quick FAQs

1. Is PTFE Teflon?

Yes. They are the same. Teflon is the brand name of PTFE.

2. Is PTFE Approved by FDA?

Yes. Virgin Polytetrafluoroethylene is approved by the Food and Drugs Authority – FDA.

3. Is PTFE Plastic or Rubber?

It is neither plastic nor rubber.

4. How does PTFE and PVC Compare?

Although both materials have the best wearing and durable features, PTFE has a longer life-span and is able to maintain its color and performance more.

Conclusion

PTFE material’s characteristic of being non-stick and easily machinable makes it one of the famous materials used in various applications.

Where its limitations are concerned, adding fillers can sort most of them out. This means, you stand to gain from its use in numerous ways.

For all your PTFE materials, contact us now.