PTFE (Unfilled)

PTFE (Polytetrafluoroethylene) resin was invented by DuPont in 1938. The extraordinary characteristics of PTFE make it the ideal choice in a wide range of products and applications. PTFE boasts the highest chemical resistance and the lowest coefficient of friction of all polymers available. It can withstand a wide range of temperatures, from cryogenic to 550 degrees F. PTFE is extremely corrosion resistant, especially to acids, and harsh inorganic and organic chemicals, it retains its properties even after extended periods in water.

As a plane bearing material, PTFE in its unfilled form does not perform well as it has very little creep strength. However, when modified with filler materials like Glass, Ceramic, Bronze, Moly or Polyimide; it becomes an excellent bearing with Limiting PV values of up to 10,000. It is easily machined with conventional metal working equipment and is available in rod, sheet, tubing as well as custom tubular bar.

Specification Test Value Units
Specific Gravity, 73°F D792 2.22
Tensile Strength @ Yield, 73°F D638 3,000 psi
Tensile Modulus of Elasticity, 73°F D638 psi
Tensile Elongation (at break), 73°F D638  270 %
Flexural Strength, 73°F D790 20,000 psi
Flexural Modulus of Elasticity D790 psi
Shear Strength, 73°F D732 psi
Compressive Strength – Ultimate 50 psi
Compressive Strength at 2% Deformation D695 100 psi
Compressive Strength at 10% Deformation D695 500 psi
Deformation Under Load %
Compressive Modulus of Elasticity, 73°F D695
Compressive Strength ⊥ to Laminate (Modulus) psi
Compressive Strength ⊥ to Laminate (Yield) 100 psi
Compressive Strength ⊥ to Laminate (Ultimate) 100 psi
Hardness, Durometer (Shore “D” scale) D2240 D60
Hardness, Rockwell (Scale as noted) D785 Rockwell M
Izod Impact, Notched @ 73°F D256 Type A ft.lbs/in. of notch
Coefficient of Friction (Dry vs Steel) Static PTM 55007 0.15
Coefficient of Friction (Dry vs Steel) Dynamic PTM 55007 0.10
Maximum Static Bearing Load (P) PTM 55007 50 psi
Maximum Unlubricated No Load Bearing Velocity (V) PTM 55007 200 ft/minute
Maximum Limiting PV (Unlubricated) PTM 55007 1,000 psi x ft/min.
Wear Factor “K” x 10-10 PTM 55010 Cubic in.-min/
Sand Wheel Wear/Abrasion Test  20 UHMW=100
Minimum Mating Surface Hardness 20 Rockwell (Brinnell)
Coefficient of Linear Thermal Expansion E-831 (TMA) 6.0 in/in/°F x 10-5
Coefficient of Thermal Expansion // to Laminates E-831 (TMA) 6.0 in/in/°F x 10-5
Coefficient of Thermal Expansion I to Laminates E-831 (TMA) 6.0 in/in/°F x 10-5
Softening Point °F
Heat Deflection Temperature 264 psi D648 °F
Embrittlement Temperature Cryogenic °F Min.
Continuous Service Temperature in Air 550 °F Max.
Short Term Service Temperature 550 °F Max.
Tg-Glass Transition (Amorphous) D3418  635 °F
Melting Point (Crystalline) Peak D3418 °F
Thermal Conductivity F433 BTU-in/(hr/ft2°F)
Dielectric Strength Short Term D149 200 Volts/mil
Volume Resistivity D257 ohm/cm
Surface Resistivity D257 ohm/cm
Dielectric Constant, 106 Hz D150
Dissipation Factor, 106 Hz D150
Flammability @ 3.1mm(1/8 in.) UL94 UL94  V-0
Arc Resistance seconds
Water Absorption, Immersion 24 Hours D570 (2) Nil %
Water Absorption, Immersion Saturation D570 (2) Nil %
Machinability Rating 7 1=easy, 10=difficult
Tubing Diameter Availability (Off the Shelf) .50 36 inches
Sheet Thickness Availability (Off the Shelf) .030 4.0 inches
Characteristics / Attributes Superior Chemical Resistance / Self Lubricating / Inert / Lowest Coefficient of Friction