What Is PTFE?
PTFE (polytetrafluoroethylene) — commercialized as Teflon — was discovered accidentally by DuPont chemist Roy Plunkett in 1938. Its extraordinary inertness comes from carbon-fluorine bonds among the strongest in organic chemistry, with fluorine atoms forming a continuous protective sheath around the carbon backbone.
PTFE resists concentrated acids, alkalis, organic solvents, and oxidizing agents. The only known substances affecting it under normal conditions are molten alkali metals and certain fluorinating agents — making it the specification of last resort when no other plastic will survive.
Key Properties
Chemical resistance: Virtually all industrial chemicals across the full pH range. Unmatched by any other standard engineering plastic.
Temperature range: -328°F to +500°F continuous — the widest of any standard engineering thermoplastic. Maintains flexibility even at cryogenic temperatures.
Coefficient of friction: The lowest of any solid material (~0.05-0.10 static). Standard for bearing surfaces and low-friction liners where no lubrication is possible.
Non-stick surface: Nothing bonds to PTFE under normal conditions — both its most famous property and a genuine fabrication challenge.
Electrical insulation: Exceptional dielectric properties across a wide frequency range. Preferred for high-frequency and microwave applications.
Biocompatibility: Non-toxic, approved for implantable medical devices and food contact.
Flame resistance: Non-flammable and self-extinguishing.
PTFE's limitations are equally important: low stiffness, poor creep resistance under sustained load, cannot be melt-processed, and significantly more expensive than nylon, Delrin, or UHMW. Specify PTFE only when its unique combination of properties is genuinely required.
Applications
PTFE Grades
Standard for most chemical resistance and electrical insulation applications. Full breadth of chemical and thermal properties.
Improved compressive strength and creep resistance. Retains most chemical resistance except hydrofluoric acid and strong alkalis which attack the glass fibers.
Better stiffness, thermal conductivity, and wear resistance. Preferred for bearing and wear pad applications.
High-load, high-speed bearing applications where thermal conductivity dissipates friction heat.
Frequently Asked Questions
Is PTFE the same as Teflon?
Yes. Teflon is Chemours' (formerly DuPont's) trade name for PTFE. Both refer to the same fluoropolymer. Other trade names include Fluon and Polyflon.
What chemicals is PTFE not resistant to?
Molten alkali metals (sodium, potassium), elemental fluorine at high temperatures, and certain fluorinating agents like chlorine trifluoride. For virtually all other chemical environments, PTFE is the correct specification.
Can PTFE be bonded or welded?
Standard adhesives won't bond to PTFE's non-stick surface. Bonding requires surface etching with sodium naphthalene solution, specialized adhesive systems, or mechanical fastening.
How does PTFE compare to UHMW for low-friction?
PTFE has lower friction and is correct when chemical resistance or high temperature is also required. UHMW offers significantly better abrasion resistance and compressive strength at much lower cost — preferred for wear pads and chute liners where chemical exposure is limited.
Where can I buy PTFE?
Plastic-Craft Products stocks virgin and filled PTFE in rod, sheet, and tube at West Nyack, NY. No minimum orders. Call (845) 358-3010 or email [email protected].
Ready to Order PTFE?
Plastic-Craft stocks virgin and filled PTFE in a full range of sizes — cut to exact dimensions with no minimum orders and ISO/AS9100D certified quality for aerospace and chemical processing programs.
(845) 358-3010