1. Chemical Structure and Properties
Molecular Formula: (C₂F₄)ₙ
Structural Formula:
A linear polymer of tetrafluoroethylene (CF₂=CF₂), with a carbon-fluorine backbone and high symmetry.
Physical Properties:
Appearance: White, waxy solid (powder, granules, or molded forms).
Melting Point: ~327°C (sintering temperature); Density: 2.1–2.3 g/cm³.
Thermal Stability: Stable from -200°C to +260°C; decomposes above 350°C, releasing toxic gases (e.g., HF, COF₂).
Chemical Properties:
Inertness: Resistant to all chemicals (acids, bases, solvents) due to strong C-F bonds and low surface energy.
Electrical Insulation: Dielectric constant ~2.1; non-conductive even at high frequencies.
Tribological Properties: Extremely low coefficient of friction (μ ~0.05–0.10).
2. Industrial Applications
Non-Stick Coatings:
Cookware: Teflon® coatings for frying pans and bakeware.
Industrial Linings: Anti-corrosion linings for chemical reactors and pipelines.
Seals & Gaskets:
Automotive/Aerospace: High-temperature seals in engines and fuel systems.
Semiconductor Manufacturing: Ultra-pure gaskets for cleanroom equipment.
Electrical Engineering:
Wire & Cable Insulation: Used in high-voltage and high-frequency applications.
Medical Devices:
Catheters & Implants: Biocompatible coatings to reduce friction and infection risks.
Textiles:
Waterproof Fabrics: Gore-Tex® membranes for outdoor apparel.
3. Safety and Toxicology
Health Hazards:
PTFE Itself: Inert and non-toxic; classified as biologically inert (ISO 10993 compliant).
Thermal Decomposition:
Above 350°C: Releases perfluoroisobutylene (PFIB) and hydrogen fluoride (HF), both highly toxic.
Pyrolysis Products: Linked to "polymer fume fever" (flu-like symptoms in humans).
Handling Precautions:
Machining: Use ventilation and PPE (respirators, gloves) to avoid inhaling fine particles.
Sintering: Avoid overheating; monitor for gas emissions.
4. Environmental and Regulatory Compliance
Environmental Impact:
Persistence: Does not degrade naturally; classified as a PBT (Persistent, Bioaccumulative, Toxic) substance in some jurisdictions.
Microplastics: PTFE particles are emerging concerns in aquatic ecosystems.
Regulatory Frameworks:
EU REACH: Restricted in consumer products if decomposed to PFAS (per- and polyfluoroalkyl substances).
U.S. EPA: Monitoring PFAS derivatives; TSCA regulations apply to PTFE production emissions.
China GB Standards: Classified as non-hazardous but subject to PFAS emission controls.
Recycling:
Mechanical Recycling: Limited due to high melt viscosity; regrind PTFE is reused in low-grade applications.
Pyrolysis: High-temperature decomposition to recover fluorinated gases (controversial due to toxicity).
5. Case Studies and Application Insights
Case 1: Semiconductor Manufacturing (ASML, 2023):
Application: PTFE seals in EUV lithography machines to prevent contamination.
Result: Enabled<1 nm chip fabrication with zero particle generation.
Case 2: Sustainable Cookware (GreenPan®, 2022):
Innovation: Replaced traditional PTFE with ceramic-reinforced coatings to eliminate PFAS concerns.
Market Impact: 50% sales growth in eco-conscious markets.
Comparative Analysis:
PTFE vs. PFA (Perfluoroalkoxy):
Pros: PTFE has higher thermal stability and lower friction.
Cons: PFA is melt-processable, allowing easier molding.
PTFE vs. Ceramic Coatings:
Pros: PTFE offers superior non-stick performance.
Cons: Ceramics avoid PFAS risks but have shorter lifespans.
Specifications：
PTFE (Polytetrafluoroethylene) is a durable, high-performance chemical with excellent chemical resistance and electrical insulation properties, ideal for diverse industrial applications, available at competitive pricing from China Amines Co.