Expanded PTFE vs PTFE: What’s the difference?

Categories: Technical Information

We all know PTFE, the grandfather of fluoroplastics, but what is expanded PTFE? Also known as ePTFE, expanded PTFE is the microporous version of PTFE. ePTFE enjoys similar properties to PTFE and is perfect for any applications that require a permeable PTFE material.

PTFE: The grandfather of fluoroplastics
The unique properties of PTFE
PTFE is the most unusual fluoropolymer and exhibits the best performance in terms of temperature, chemical resistance and non-stick properties. In addition, PTFE also enjoys the following benefits:

Best price : performance ratio

Continuous working temperature of +260°C – This is the highest working temperature for any fluoroplastic

Low friction surface

Very high electrical resistance

Translucent colour – When the correct raw polymer grade is chosen

PTFE applications
Thanks to its unique properties, PTFE is able to endure even the harshest of environments and as such, is suitable for use in numerous applications. PTFE material is ideal for use in the food and drink production, from cooking equipment to food coverings, conveyor belt rollers, temperature sensor casing and non-stick surface covers.

PTFE material is particularly useful for medical applications and for the production of internal and external life-saving equipment such as catheters, bio-containment vessels, syringes and sutures. This unique fluoropolymer is also perfect for electrical insulation and the protection of electronic components. In the chemical industry, PTFE can be used to make different products, from gaskets to vessel linings and chemical tanks.

Expanded PTFE: The microporous fluoropolymer
What is ePTFE?
Expanded PTFE (ePTFE) tube is microporous so air-permeable, and is perfect for any applications that require a permeable material. As such, ePTFE is different to conventional PTFE. The material is soft and flexible, and feels somewhat like smooth, spongey marshmallow to the touch. Expanded PTFE is often used in the form of cord, sealing tape or tubing.

The benefits of expanded PTFE
Expanded PTFE shares similar properties to PTFE. The material is completely non-toxic and hygienic, and also offers working temperatures up to 260°C. In addition, ePTFE enjoys the following benefits:

Chemically resistant with high linear strength

Chemically inert

Watertight at low pressure

Low dielectric constant

Excellent radial expansion and UV resistance

Different levels of porosity available – Low, medium and high density

Applications for ePTFE
Thanks to its permeable property, expanded PTFE is ideal for use in medical devices, electronic insulators, high performance filters and various other applications. In oil and gas, this porous fluoroplastic is usefully applied to chemical pipe flanges to even out any bumps and ridges in the pipes and achieve a truer seal.

ePTFE is also used to produce a mesh-like structure for implants, which whilst being soft, strong and flexible, is also very porous. When implanted, this allows body-tissue to grow seamlessly into it, making it an excellent material for use in vascular grafts, hernia repair and other reconstructive surgery.

Expanded PTFE is perfectly suited for environmental filtration and fluidic purification applications. We worked on a project to purify water using ePTFE tubing. Our customer flowed some Ozone gas through expanded PTFE tubing, which then leaked out into the iron-rich water and purified it. As a result, the water purification technology with the help of this unique fluoroplastic helped deliver clean, safe water.