What is PTFE?

Polytetrafluoroethylene (PTFE) is a synthetic material accidentally invented in the late 1930s while a chemist was endeavoring to develop a new type of perfluorethylene-based refrigerant. Rather than achieving a chlorofluorocarbon, the scientist was surprised to find that the perfluorethylene used in the process reacted with the iron content of its container and polymerised under pressure. Less than a decade later, this new material was being distributed on a commercial scale and was eventually patented under the name Teflon®.

Polytetrafluoroethylene (PTFE) is formed by the polymerisation of tetrafluoroethylene (TFE). The basic properties of PTFE stem from a very strong chemical bond between the carbon and fluorine atoms. PTFE has a most unique position in the plastics industry because of its chemical inertness, heat resistance, excellent mechanical, dielectric, anti-adhesion properties and low coefficient of friction over a broad service temperature and pressure ranges. The above properties assure wide application of this material in all industrial sectors.

During WWII, PTFE was used in the Manhattan Project to prevent the escape of radioactivity from the facility designated to produce the first atom bomb. The uranium hexafluoride was housed on an impressive piece of real estate measuring more than 2 million square feet (609,600 sq m). Apart from being highly toxic and corrosive in itself, it forms hydrogen fluoride, a dangerous gas, in the presence of moisture. PTFE was therefore used to coat the pipes, in order to make them leak proof.

The exceptional insulating properties of PTFE made it ideal for use in electronic components. First, it is non-conductive, which makes it resistant to high electric fields. Furthermore, it is highly resistant to water, heat, and chemical corrosion. As a result, its is also used to make laboratory equipment that comes into contact with hydrofluoric acid, which dissolves other materials, even glass.

PTFE also possesses very low frictional properties, traditionally represented by the term coefficient of friction. This measurement is relative and differs according to the materials brought into contact to generate or simulate friction. For plastics, friction is usually observed against polished steel. To place the low friction coefficient of PTFE in perspective, it is the only known synthetic surface material to which the toe pads of a gecko fail to stick. This quality makes it suitable for manufacturing parts that need to resist friction, such as gears and ball bearings.

PTFE is made up of carbon and fluorine atoms. The fluorine atoms are just the right size to form a helical shield around the carbon atoms. Because nothing can get close enough, this prevents any chemical attack on the carbon atoms. Fluorine is an extremely reactive element and the chemical bond between it and carbon is one of the strongest in organic chemistry. This is why PTFE can be attacked under only extreme conditions. The forces between polymer chains are extremely small, which gives PTFE its excellent low coefficient of friction.

At JD Jones

We specialise in manufacturing PTFE/RPTFE/TFM machined component from resin by moulding, sintering and machining for a range of industries such as valve manufacturers, aerospace, semi-conductors, corrosive chemical plants, cryogenic valves, petrochemicals, oil and gas. We also offer semi-finished products including rods, tubes and sheets. Our materials are assuredly of the highest quality through mechanical property testing. All of our materials are tested on-site to International Standards so that we can maintain a product of a consistent quality without impacting on lead times.

Beneficial Properties

  • Superior chemical resistance
  • Low coefficient of friction
  • Near zero stick/slip force
  • Wide temperature range
  • Low moisture absorption
  • High electrical resistance
  • FDA approved grades available

Materials Include

PTFE, TFM, RPTFE such as carbon filled, glass filled, glass + MoS2 filled, glass + graphite + carbon filled, calcium metasilicate filled, carbon filled with ECG alloy 88, PEEK filled and many more.

Test Parameter Virgin PTFE 25% Glass Filled PTFE 15% Carbon Filled PTFE 25% Carbon Filled PTFE 15% Glass Filled PTFE 60% Bronze Filled PTFE 55% Br + 5% MOS2
Filled PTFE
10% glass + 9.4% Carbon + 0.6% Graphite filled PTFE(RTFE) 20% Glass + 5% MOS2 filled PTFE 15% Graphite Filled PTFE 17% Peek + 3% MOS2 filled PTFE 12% Calcium
Metasilicate + 3% MOS2 Filled PTFE
20% Peek Filled PTFE 35% Carbon Filled PTFE TFM 15% Glass + 9.4% Carbon + 0.6% Graphite Filled PTFE (RTFE) 15% Peek Filled PTFE 50% SS Filled PTFE
Colour Milky White Off White Grey Grey Off White Brownish Brownish Blackish Grey Off White Dark Grey Grey Dark Grey Ash Milky White Blakish Grey Ash
Filler Content (%) Nil 25% Glass 15% Carbon 25% Carbon 15% Glass 60% Bronze 55% Br + 5% MOS2 10% Glass + 9.4% Carbon + 0.6% Graphite 20% Glass + 5% MOS2 15% Graphite 17% Peek + 3% MOS2 12% Calcium Metasilicate + 3% MOS2 20% Peek 35% Carbon NIL 15% Glass + 9.4% Carbon + 0.6% Graphite 15% Peek 50% Stainless steel
Tensile Strength (PSI) 3700 min 2465 min 2320 min 1775 min 2415–3408 1420–2840 1562–2274 3124–3905 2840–3408 1990–2698 1704–2556 3000 min 1735 min 1420–2485 4047 min 2897 min 2030 min 2158 min
Compressive Strength (kgf/cm2) 40–50 75–85 65–75 75–85 65–75 115–125 115–125   65–75 65–75 55–75   55–75 80–90 45–55   56–76  
Elongation (%) 275 min 210 min 210 min 110 min 270–350 150–300 150–300 170–210 240–320 180–230 140–180 200 min 145 min 90–125 400 min 180 min 180 min 150 min
Hardness (Shore D) 50–65 60–65 60–65 70–75 58–62 64–68 64–68 62–64 60–65 60–65 63–65 62 min 60–65 72–80 56–62 62–64 63–65 60–65
Specific Gravity (g/cc) 2.13–2.19 2.2–2.25 2.1–2.15 2.12–2.14 2.15–2.22 3.8–4.0 3.8–4.0 2.16 min 2.20–2.24 2.10–2.16   2.24 min 1.6–1.9 2.11-2.13 2.15–2.2 2.16 min 1.93–1.96 3.36–3.4
Working Temperature Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C Up to 250°C

Valve Seats

Valve seats and seats are can be made using PTFE, RPTFE, TFM. At JD Jones, these products are available in a range of dimensions and profiles and are customisable based on customer requirements and OEM drawings.

Aside from standard parts, we also manufacture customised components to suit specific customer requirements and end-use applications.

Our Products Includes

  • PTFE and RPTFE back-up rings
  • Thrust washers
  • Ball Valve Seats
  • Butterfly Valve Seats
  • Piston Ring Seals
  • Rotary Shaft Seals
  • Spring-energised Seals
  • Actuator Joint Bush
  • PTFE/RPTFE Specialised Gaskets