PTFE Sheet: Properties, Processing & Industrial Applications Guide

Key Advantages of PTFE

Ultimate Chemical Resistance

PTFE is virtually inert to all known chemicals except molten alkali metals (sodium, potassium) and elemental fluorine at high temperatures. No acid, base, solvent, or oxidiser can attack PTFE at normal service temperatures.

Lowest Friction Coefficient

With a coefficient of friction of 0.05–0.10, PTFE is one of the slipperiest solid materials known. This makes it ideal for:

· Sliding bearings

· Non-lubricated seals

· Release surfaces for moulding

· Anti-friction linings

Widest Temperature Range

PTFE operates from –200°C to +260°C continuously — the widest range of any engineering plastic. This covers cryogenic applications through to high-temperature chemical processing.

Electrical Insulation

PTFE‘s low dielectric constant (2.1) and negligible dissipation factor make it the premier material for high-frequency and microwave applications. It is used in RF connectors, coaxial cable insulation, and PCB substrates.

Limitations of PTFE

Low Mechanical Strength

PTFE‘s tensile strength (25 MPa) is the lowest among engineering plastics — lower than PEEK (98 MPa), POM (70 MPa), and PA66 (85 MPa). It cannot carry significant structural loads.

Cold Flow (Creep)

PTFE exhibits significant cold flow under load, even at room temperature. This means it gradually deforms under sustained stress, making it unsuitable for precision dimensional applications without reinforcement.

High Thermal Expansion

PTFE‘s CLTE (12 × 10⁻⁵/°C) is 3–5× higher than other engineering plastics. Components will change dimensions significantly with temperature changes.

Processing Difficulty

PTFE cannot be melt-processed by conventional injection moulding or extrusion due to its extremely high melt viscosity. It is processed by sintering (compression moulding + baking), limiting part complexity.

Common Applications

Chemical Processing

· Gaskets and seals — chemical line flange gaskets

· Valve seats and seals — corrosion-free sealing

· Pump diaphragms — chemical resistance + flex

· Tank linings — corrosion protection

· Pipe linings — chemical transport

Food & Beverage

· Non-stick conveyor belts — baking and food processing

· Release sheets — moulding and forming

· Sealing gaskets — FDA compliant

Electrical & Electronics

· RF/microwave components — low dielectric

· Cable insulation — high-temperature wires

· PCB substrates — high-frequency boards

· Connector insulators — high voltage

Industrial

· Slide bearings — low friction, no lubrication

· Expansion joint materials — thermal flexibility

· Shaft seals — wear and chemical resistance

For comparison with PEEK, see our PEEK vs PTFE guide. For material overview, read our Engineering Plastics Overview.