PTFE History

PTFE was the original discovery of TEFLON by DuPont researcher Dr. Roy Plunkett as he was working with refrigerants. Upon checking a frozen, compressed sample of tetrafluoroethylene, he discovered that the sample had polymerized spontaneously into a white, waxy solid, which he called polytetrafluoroethylene (PTFE).

DuPont engineers were then able to convert PTFE into blocks, which could then be machined into desired shapes. Later on, aqueous dispersion were developed, followed by powder grades for extruded tubing.

The Steel Industry and Chemical Processing Industry have been using TEFLON tubing and hoses for many years for transferring highly caustic or corrosive chemicals. More and more, TEFLON tubing is replacing carbon and other metal piping that deteriorates rapidly.

And while some manufacturers use TEFLON to produce their products, others use it as part of their products. Now and for the future, TEFLON will continue to serve the industry in critical applications.

Manufacturing Process of PTFE:

CHCL3 + 2 HF CHClF2 + 2 HCl
2 CHClF2 CF2 = CF2 + 2 HCL
n CF2 = CF2 (-CF2 – CF2 -) n
Tetra-Fluoro-Ethylene (TFE) (PTFE)


Chemical Qualities*: PTFE is inert to the following chemicals

Inorganic Chemicals Organic Chemicals Other
Aqua Regia Alcohols Biological Fluids
Hydrofluoric Acid Esters Fragrances
Fuming Sulfuric Acid Ketones Food
Chlorosulfuric Acid Highly Halogenated Organics Printing Inks & Dyes
Boiling Sodium Hydroxide Solution Aromatic Solvents Low Level Radioactive Substances
Chlorine Gas Amines Oxidizers
Hydrogen Peroxide Industrial Oils
Acid Chlorides
Hot, Fuming Nitric Acid

*Among the only chemicals known to attack PTFE are molten alkali metals and their solutions, chlorine trifluoride, and gaseous fluorine at elevated temperatures and pressures.

Thermal Qualities:

PTFE can withstand temperatures up to 680 °F for limited periods of time.* Under cryogenic conditions, PTFE remains strong down to -320 °F.

*Above 500 °F, mechanical properties become a limiting factor

Electrical Qualities:

PTFE has superb electrical properties, indicated by a low dielectric constant of 2.1 between -40 °F and 480 °F within a frequency range of 5 Hz to 10 GHz.

PTFE is also an excellent insulator with surface resistivity of 3.6 X 1012 ohms (even at 100% relative humidity).

Short time dielectric strengths range from 500 volts/mil (1 mil = 10-3 in) for thicknesses greater than 100 mils to 4000 volts/mil for very thin films.

UV and Radiation Qualities*:

PTFE has excellent UV resistance and weatherability, with a radiation dose threshold for PTFE at 2 – 7 X 104 rads. Absence of oxygen increases radiation resistance by a factor of at least 10.

*Resistance to electron and gamma radiation is relatively poor

Wear and Friction Qualities:

PTFE has a relatively slippery and smooth surface, with a static coefficient of friction of 0.08 and 500 psi load.

The properties of PTFE make it particularly suitable for use as bearing pads, under high pressure-low velocity load conditions. Examples are bridge bearing pads, pipe support pads, and mounting pads for heavy manufacturing.

Short List Applications:

  1. Heat Shrink & Non-Shrink Tubing
  2. Heat Exchangers
  3. Coatings
    1. Carburetor Shafts
    2. Medical Catheter Guide Wires
    3. Mold Release
    4. Cryogenic Applications
    5. Automotive Brake Parts
    6. Jet Fuel Filters
    7. Bearing Pads

Chemical Reasoning for PTFE Properties

High C-F Bond Strength & No UV Absorption Sites Thermal Stability
Oxidative Stability
Non-Flammability
Chemical Resistance
Resistance to Weathering
Enormous Chain Length High Melt Viscosity
Low Inter-chain Forces Excellent Toughness
Low Coefficient of Friction
Low Forces Between F Atoms and Molecules Insolubility
Low Solvent Absorption
High Crystallinity Non-Stick Properties
Low Water Absorption
No Permanent Dipole Low Dielectric Constant
No Surface Chemistry High Static Charge