This article understands four kinds of fluorine plastics: PTFE, ETFE, FEP, PFA

The history of fluoroplastics began in 1934 when F. Schloffer and O. Scherer from the German company I.G. Farbenindustrie invented polychlorotrifluoroethylene (PCTFE). This was followed by Dr. Plunkett of DuPont's discovery of polytetrafluoroethylene (PTFE) in 1938, marking the inception of fluoropolymer research and applications.

Subsequently, driven by market demand and technological advancements, various fluoroplastics were successively developed:

• 1955: Vinylidene fluoride-chlorotrifluoroethylene copolymer (VDF-CTFE)
• 1960s: Polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), and ethylene-chlorotrifluoroethylene copolymer (ECTFE)
• 1970s: Perfluorosulfonic acid resin (XR resin), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), ethylene-tetrafluoroethylene copolymer (ETFE), and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA)

Exceptional Properties of Fluoroplastics

The presence of fluorine atoms endows fluoroplastics with remarkable characteristics:

• Outstanding flame retardancy and stability
• Superior electrical insulation and mechanical performance
• Excellent heat resistance (up to 260°C)
• Exceptional oil, solvent, and wear resistance
• Strong moisture resistance and low-temperature tolerance (-200°C)

These properties make fluoroplastics indispensable in fields such as defense, aerospace, semiconductors, electronics, construction, healthcare, automotive, machinery, metallurgy, and petrochemical industries.

Common Fluoroplastics: PTFE, ETFE, PVDF, FEP, PFA

1. PTFE (Polytetrafluoroethylene)

PTFE, a polymer derived from tetrafluoroethylene, is renowned as the "King of Plastics" due to its:

• Extreme temperature resistance (-268.785°C to 260°C)
• Chemical inertness (resistant to nearly all chemicals)
• Ultra-low friction coefficient and non-stick properties
• Superior dielectric strength (withstands 1,500V)
• Biocompatibility (used in medical implants)

Applications:

• High-frequency cables, bearings, seals, and non-stick coatings (e.g., cookware, waterproof textiles)
• 5G components (high-frequency circuit boards, antenna filters)
• Industrial filtration membranes and protective gear

Limitations:

• Poor adhesion to metals
• Limited mechanical strength

2. ETFE (Ethylene-Tetrafluoroethylene Copolymer)

Developed in 1970 by NASA and DuPont for spacecraft radiation shielding, ETFE combines PTFE’s corrosion resistance with enhanced mechanical properties:

• Twice the tensile strength of PTFE (~50 MPa)
• 95% light transmittance and B1 fire rating
• Thermal expansion coefficient similar to carbon steel

Applications:

• Architectural membranes (e.g., Beijing’s Water Cube, Munich’s Allianz Arena)
• Composite materials for pipes and anti-corrosion coatings

3. FEP (Fluorinated Ethylene Propylene Copolymer)

A modified PTFE with branched molecular structure:

• Retains PTFE’s chemical resistance
• Thermoplastic processability (-85°C to 200°C service range)
• Lower mechanical strength than engineering plastics

Applications:

• Wire/cable insulation (aircraft, oil wells)
• Solar panel coatings

4. PFA (Perfluoroalkoxy Alkane)

A melt-processable PTFE variant:

• Matches PTFE’s performance (300–310°C melting point)
• Higher viscosity than FEP during processing

Applications:

• Semiconductor equipment linings
• High-purity chemical containers

5. PVDF (Polyvinylidene Fluoride)

Introduced commercially in 1960, PVDF excels in:

• Mechanical rigidity and UV resistance
• Piezoelectric properties (used in sensors/batteries)
• Processability via injection molding

Applications:

• Lithium-ion battery binders
• Chemical piping and architectural coatings

Trade-offs

While fluoroplastics offer unparalleled performance, limitations persist:

• PTFE: Adhesion challenges
• ETFE: Lower thermal tolerance than PTFE
• PFA: High cost
• FEP: Reduced mechanical strength

These materials continue to evolve, driven by demands from advanced industries like renewable energy and 5G technology.