Perfluoroalkoxy alkane PFA

Copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether, (-CF2-CF2-)m-(CF2-CF(ORf)-)n · CAS 26655-00-5

PFA is a fully fluorinated, melt-processible copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether that combines the chemical inertness and continuous high-temperature service up to 260 °C with conventional thermoplastic fabrication.

10 sources · Updated 2026-10-20 · CC BY 4.0

Evidence level

5 of 5

Flown or field-proven

Recipe, share of the weight

  • not statedTetrafluoroethylene
  • not statedPerfluoroalkyl vinyl ether

Best for

Melt-processible thin films, wire insulation, and fluid components requiring extreme chemical inertness, low outgassing, and resistance to atomic oxygen erosion in low Earth orbit.

Weakest at

Low resistance to ionizing radiation (chain scission causes embrittlement above 10 kGy), modest mechanical tensile strength of 21 MPa, and release of corrosive hydrogen fluoride upon heating above 350 °C.

Risk at a glance

  • People No data. No hazard data recorded
  • If it fails High. Radiation embrittlement
  • Corrosion Severe. Overheating above 350 °C causes decomposition and releases toxic hydrogen fluoride.

Quick facts: PFA

Key properties of PFA
PropertyValueBasis
Density2.14 to 2.15 g/cm³2 sourced values across conditions
Yield strength12 MPa1 sourced value
Tensile strength21 MPa1 sourced value
Young's modulus0.48 GPa1 sourced value
Thermal conductivity0.2 W/(m·K)1 sourced value
Melting point302 to 310 °C2 sourced values across conditions
Specific heat1,172 J/(kg·K)1 sourced value
Maximum service temperature260 °C1 sourced value

What is the density of Perfluoroalkoxy alkane (PFA)?

Perfluoroalkoxy alkane (PFA) has a density of 2.14 to 2.15 g/cm³. The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.

What is the thermal conductivity of Perfluoroalkoxy alkane (PFA)?

Perfluoroalkoxy alkane (PFA) has a thermal conductivity of 0.2 W/(m·K). The source and test conditions are listed in the properties table on this page.

What is the melting point of Perfluoroalkoxy alkane (PFA)?

Perfluoroalkoxy alkane (PFA) has a melting point of 302 to 310 °C. The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.

What is the yield strength of Perfluoroalkoxy alkane (PFA)?

Perfluoroalkoxy alkane (PFA) has a yield strength of 12 MPa. The source and test conditions are listed in the properties table on this page.

What is the tensile strength of Perfluoroalkoxy alkane (PFA)?

Perfluoroalkoxy alkane (PFA) has a tensile strength of 21 MPa. The source and test conditions are listed in the properties table on this page.

What is Perfluoroalkoxy alkane (PFA) used for?

Uses recorded in the sources include High-temperature wire and cable insulation; High-purity fluid handling tubing, valve linings and containment fittings.

Why it exists

PFA provides the chemical inertness, low dielectric constant of 2.0, and continuous operating service up to 260 °C characteristic of PTFE, but adds the capability of melt extrusion and injection moulding. In low Earth orbit exposure on MISSE 2, its measured atomic oxygen erosion yield was 1.73e-25 cm3/atom, and its vacuum outgassing total mass loss is 0.01 percent.

Where it's used

Use

High-temperature wire and cable insulation where dielectric stability and continuous rating to 260 °C are needed.

Use

Chemical process and fuel fluid handling components requiring resistance to aggressive propellants.

Use

Low-outgassing films in vacuum systems where total mass loss of 0.01 percent satisfies ASTM E595 requirements.

Recipe

Copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether, (-CF2-CF2-)m-(CF2-CF(ORf)-)n; CAS 26655-00-5

PFA is a fully fluorinated copolymer of tetrafluoroethylene and a perfluoroalkyl vinyl ether comonomer. The repeating structure consists of linear tetrafluoroethylene units interspersed with bulky perfluoroalkoxy pendant groups that lower crystallinity and allow thermoplastic melt processing.

What PFA is made of
IngredientShare of the weightWhat it does
Tetrafluoroethylene not stated Primary fluorinated backbone monomer providing chemical inertness and low friction
Perfluoroalkyl vinyl ether not stated Comonomer whose bulky perfluoroalkoxy pendant group disrupts crystalline packing to enable melt extrusion

Weight shares are as printed in the sources.

What it can do

Strength

PFA achieves a tensile strength of 21 MPa and an elongation of 300 percent at break under ASTM D882 testing.

Thermal

PFA retains structural integrity with a Vicat softening temperature of 287 °C and a heat distortion temperature of 91 °C at 0.45 MPa.

Electrical

PFA exhibits a low dielectric constant of 2.0 and a dielectric strength of 260 kV/mm on thin films.

How it compares

Among fluoropolymers evaluated on MISSE 2, PFA erodes under atomic oxygen at 1.73e-25 cm3/atom, performing closely to FEP and PTFE. Unlike PTFE, PFA is melt-processible with a melting range of 302 to 310 °C, and maintains a tensile strength of 21 MPa with an elongation of 300 percent at room temperature.

The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Other materials are shown beside it; each was measured under its own conditions, so open its page before comparing closely. Compare every grade in the family.

Benchmarks
MeasurementPFAAFPCTFE (CTFE, Kel-F)ECTFE (Halar)ETFEFEPPTFEPVDF (Kynar)PVFPVF (white Tedlar)
Thermal behavior and safety
Melting range, Teflon PFA film (ASTM D3418)302 °C4no data210 °C238 °C265 °C255 °Cno datano datano data185 °C
Melting point, Teflon PFA 440HPB (ASTM D4591)305 °C5no data210 °C238 °C265 °C255 °Cno datano datano data185 °C
Thermal conductivity, Teflon PFA film (Cenco-Fitch)0.195 W/(m·K)13no datano data3.75×10^-4 cal/cm-sec-°Cno datano datano datano datano datano data
Specific heat capacity, Teflon PFA film1172 J/(kg·K)14no datano datano datano datano datano datano datano data1.05 kJ/kg K
Heat distortion temperature at 0.45 MPa (JIS K7207)91 °C15156 °Cno data115 °Cno datano datano data125 °Cno datano data
Lifetime and stability
Total mass loss, Teflon PFA molded resin (ASTM E595)0.01 % mass24no datano datano datano datano data0 % massno datano datano data
Collected volatile condensable material, Teflon PFA molded resin (ASTM E595)0 % mass25no datano datano datano datano data0 % massno datano datano data
Physical and electrical
Density (MISSE 2 flight sample)2.138 g/cm³22.146 g/cm³2.133 g/cm³1.68 g/cm³1.74 g/cm³2.144 g/cm³2.17 g/cm³no data1.379 g/cm³1.624 g/cm³
Density (Teflon PFA film, ASTM D1505)2150 kg/m332.146 g/cm³2.133 g/cm³1.68 g/cm³1.74 g/cm³2.144 g/cm³2.17 g/cm³no data1.379 g/cm³1.624 g/cm³
Temperature behavior
Vicat softening temperature, Fluon PFA P-66P (JIS K7206)287 °C16no datano datano datano datano datano datano datano datano data
Other measurements
Atomic oxygen erosion yield, MISSE 2 flight1.73×10^-25 cm³/atom11.98×10^-25 cm³/atom8.31×10^-25 cm³/atom1.79×10^-24 cm³/atom9.61×10^-25 cm³/atom2×10^-25 cm³/atom1.42×10^-25 cm³/atom1.29×10^-24 cm³/atom3.19×10^-24 cm³/atom1.01×10^-25 cm³/atom
Tensile strength at break, Teflon PFA film (ASTM D882)21 MPa626.9 MPa34 MPa7000 psi40 MPa20 MPano datano data8 kpsi55 MPa
Tensile strength at -198 °C (liquid nitrogen temperature)130 MPa726.9 MPa34 MPa7000 psi40 MPa20 MPano datano data8 kpsi55 MPa
Yield point, Teflon PFA film (ASTM D882)12 MPa827.4 MPano datano datano data13.8 MPano datano datano datano data
Elongation at break, Teflon PFA film (ASTM D882)300 %917.1 %100 %200 %300 %300 %no datano data90 %90 %
Elastic modulus, Teflon PFA film (ASTM D882)480 MPa101.6 GPa5.65 GPa2.4×10^5 psi1075 MPano datano datano datano data2655 MPa
Flexural modulus, Fluon PFA P-66P (ASTM D790)0.54 GPa111.8 GPano datano datano data520 MPano data1655 MPano datano data
Flexural modulus, Teflon PFA 440HPB (ASTM D790)590 MPa121.8 GPano datano datano data520 MPano data1655 MPano datano data
Continuous upper service temperature260 °C17no data175 °C149 °C150 °C204 °C260 °Cno data107 °C107 °C
Dielectric constant at 1 MHz, Teflon PFA film (ASTM D150)2 -181.93 unitlessno data2.5 none2.6 dimensionless2.03 -2.1 dimensionlessno datano data11 -
Dielectric constant at 1 MHz, Teflon PFA 440HPB (ASTM D150)2.03 -191.93 unitlessno data2.5 none2.6 dimensionless2.03 -2.1 dimensionlessno datano data11 -
Dielectric strength, short time, 0.025 mm film (ASTM D149)260 kV/mm202.1 kV/0.1 mmno data500 V/milno data80 kV/mm30 kV/mmno datano data3.5 kV/mil
Dielectric strength, short time, 0.25 mm specimen (ASTM D149)80 kV/mm212.1 kV/0.1 mmno data500 V/milno data80 kV/mm30 kV/mmno datano data3.5 kV/mil
Refractive index (ASTM D542)1.35 -221.31 unitlessno datano datano datano datano datano data1.46 nD1.46 nD
Melt flow rate, Teflon PFA 440HPB (ASTM D3307)14 g/10min23no datano datano datano data30 g/10minno datano datano datano data

Why choose it, and why not

Good for

  • Wire insulation and cable sleeving for aerospace and spaceflight electronics requiring continuous service up to 260 °C.
  • High-purity tubing and fluid handling components exposed to aggressive chemicals or vacuum conditions.
  • Thin protective films in low Earth orbit requiring low atomic oxygen erosion rates and minimal outgassing.

Watch out for

  • Ionizing radiation causes backbone chain scission with significant loss of ductility above 10 kGy.
  • Heating above 350 °C causes thermal breakdown, evolving toxic and corrosive hydrogen fluoride gas.
  • Tensile strength of 21 MPa is modest, precluding primary structural load-bearing functions.

PFA is an outstanding melt-processible fluoropolymer for aerospace wire insulation, fluid handling, and low-outgassing barrier films in low Earth orbit, provided it is shielded from high cumulative ionizing radiation doses above 10 kGy.

Technical details

For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.

Notes

The method, full conditions and any caveat for the numbered rows above.

Notes for the numbered rows
#MeasurementMethodConditionsCaveat
1Atomic oxygen erosion yield, MISSE 2 flightValue printed in NASA Table I (MISSE 2 PEACE Polymers erosion yield data) as the measured flight erosion yieldenvironment low Earth orbit, ISS MISSE 2 PEACE Polymers trayfluence 8.43e21 atoms/cm2 (3.95 year exposure)unit in source cm3/atom—
2Density (MISSE 2 flight sample)Density listed in NASA Table II for the flown PFA test sample, column Density (ref. 12)sample MISSE 2 PEACE Polymers flight film—
3Density (Teflon PFA film, ASTM D1505)Density printed in Chemours Teflon PFA Properties Bulletin, General properties sectiontest standard ASTM D1505form 0.050 mm (2 mil) film at 25 °C—
4Melting range, Teflon PFA film (ASTM D3418)Melting point range printed in Chemours Teflon PFA Properties Bulletin, Thermal sectiontest standard ASTM D3418—
5Melting point, Teflon PFA 440HPB (ASTM D4591)Melting point printed in Chemours Product Information sheet for Teflon PFA 440HPBtest standard ASTM D4591grade Teflon PFA 440HPB molding and extrusion resin—
6Tensile strength at break, Teflon PFA film (ASTM D882)Tensile strength at break printed in Chemours Teflon PFA Properties Bulletintest standard ASTM D882temperature 25 °Cform 0.050 mm (2 mil) film—
7Tensile strength at -198 °C (liquid nitrogen temperature)Tensile strength measured at low temperature (-198 °C) reported in AGC Fluon PFA technical brochuretemperature -198 °Cgrade Fluon PFA P-66P—
8Yield point, Teflon PFA film (ASTM D882)Yield point printed in Chemours Teflon PFA Properties Bulletintest standard ASTM D882temperature 25 °Cform 0.050 mm (2 mil) film—
9Elongation at break, Teflon PFA film (ASTM D882)Elongation at break printed in Chemours Teflon PFA Properties Bulletintest standard ASTM D882temperature 25 °Cform 0.050 mm (2 mil) film—
10Elastic modulus, Teflon PFA film (ASTM D882)Elastic modulus printed in Chemours Teflon PFA Properties Bulletintest standard ASTM D882temperature 25 °Cform 0.050 mm (2 mil) film—
11Flexural modulus, Fluon PFA P-66P (ASTM D790)Flexural modulus printed in AGC Fluon PFA Technical Brochure property tabletest standard ASTM D790temperature 23 °Cgrade Fluon PFA P-66P—
12Flexural modulus, Teflon PFA 440HPB (ASTM D790)Flexural modulus printed in Chemours Teflon PFA 440HPB property data tabletest standard ASTM D790temperature 23 °Cgrade Teflon PFA 440HPB—
13Thermal conductivity, Teflon PFA film (Cenco-Fitch)Thermal conductivity printed in Chemours Teflon PFA Properties Bulletinmethod standard Cenco-Fitchtemperature 25 °C—
14Specific heat capacity, Teflon PFA filmSpecific heat value printed in Chemours Teflon PFA Properties Bulletintemperature 25 °C—
15Heat distortion temperature at 0.45 MPa (JIS K7207)Heat distortion temperature under 0.45 MPa load reported in AGC Fluon PFA technical brochureload 0.45 MPa (66 psi)rate 2 °C/mingrade Fluon PFA P-66P—
16Vicat softening temperature, Fluon PFA P-66P (JIS K7206)Vicat softening temperature printed in AGC Fluon PFA technical brochureload 1 kgrate 50 °C/hgrade Fluon PFA P-66P—
17Continuous upper service temperatureUpper continuous service temperature limit stated in Chemours Teflon PFA film bulletinenvironment air, continuous service—
18Dielectric constant at 1 MHz, Teflon PFA film (ASTM D150)Dielectric constant value printed in Chemours Teflon PFA Properties Bulletinfrequency 100 Hz to 1 MHztemperature 25 °Ctest standard ASTM D150—
19Dielectric constant at 1 MHz, Teflon PFA 440HPB (ASTM D150)Dielectric constant printed in Chemours Teflon PFA 440HPB property data tablefrequency 1 MHztest standard ASTM D150 / IEC 250—
20Dielectric strength, short time, 0.025 mm film (ASTM D149)Short-time dielectric strength printed in Chemours Teflon PFA Properties Bulletintest standard ASTM D149 Method Athickness 0.025 mm (1 mil)environment air at 23 °C, 60 Hz—
21Dielectric strength, short time, 0.25 mm specimen (ASTM D149)Dielectric strength printed in Chemours Teflon PFA 440HPB property data tabletest standard ASTM D149 / IEC 243thickness 0.25 mm (0.010 in)—
22Refractive index (ASTM D542)Refractive index value printed in Chemours Teflon PFA Properties Bulletintest standard ASTM D542—
23Melt flow rate, Teflon PFA 440HPB (ASTM D3307)Melt flow rate value printed in Chemours Teflon PFA 440HPB property data tabletest standard ASTM D3307 / ISO 12086temperature 372 °Cload 5 kg—
24Total mass loss, Teflon PFA molded resin (ASTM E595)Total mass loss measured in NASA outgassing screening test per ASTM E595test standard ASTM E595temperature 125 °Cduration 24 hrpressure < 10^-5 torrspecimen TEFLON PFA MOLDED SPECIMEN TE-9704, GSFC4828—
25Collected volatile condensable material, Teflon PFA molded resin (ASTM E595)Collected volatile condensable material measured in NASA outgassing test per ASTM E595test standard ASTM E595temperature 125 °Cduration 24 hrpressure < 10^-5 torrcollector temperature 25 °Cspecimen TEFLON PFA MOLDED SPECIMEN TE-9704, GSFC4828—

Corrosion and compatibility

What happens when it meets other materials and environments.

Corrosion and compatibility
EnvironmentConcernWhat happens
Atomic oxygen in low Earth orbit (MISSE 2 flight, 3.95 years) low PFA erodes slowly under atomic oxygen in low Earth orbit.1
Reactive chemicals and aggressive solvents none PFA is chemically inert to virtually all acids and solvents.2
Thermal degradation above 350 °C severe Overheating above 350 °C causes decomposition and releases toxic hydrogen fluoride.3
Ionizing radiation (gamma, electron or proton dose) severe Radiation exposure causes chain scission and rapid loss of ductility above 10 kGy.4
Corrosion details
#EnvironmentDetailsTest conditions
1 Atomic oxygen in low Earth orbit (MISSE 2 flight, 3.95 years) Measured flight erosion yield of 1.73e-25 cm3/atom outside the ISS Quest airlock at 8.43e21 atoms/cm2 fluence. fluence 8.43e21 atoms/cm2
2 Reactive chemicals and aggressive solvents Chemours and AGC report that PFA resists virtually all chemicals except molten alkali metals, gaseous fluorine, and chlorine trifluoride at high temperature. temperature high temperature
3 Thermal degradation above 350 °C Small amounts of hydrogen fluoride evolve around 350 °C, and extended overheating above 400 °C can lead to autocatalytic degradation. temperature above 350 °C
4 Ionizing radiation (gamma, electron or proton dose) Nordion gives a gamma tolerance limit of 5 to 10 kGy, and AGC tests show marked loss of elongation at 10 Mrad in air. exposure gamma irradiation in air

Risks and side effects

Hazards to people, what happens when a cell overheats, and how the material is handled and stored.

Spacecraft harness engineers using PFA insulation in high radiation orbits

Personnel handling fluoropolymer processing equipment above 350 °C

Mission designers deploying thin PFA films in low Earth orbit atomic oxygen

Test details
The original wording and numbers from the sources, for readers who want them.

Failure risks

Failure risks
FailureTrigger and consequence
Radiation embrittlementhigh severityTotal ionizing dose exceeding 10 kGyPolymer backbone scission reduces elongation toward zero, leading to mechanical cracking under vibration or thermal strain.
Atomic oxygen surface erosionmoderate severityExposure to orbital atomic oxygen fluenceSurface mass loss occurs at 1.73e-25 cm3/atom in low Earth orbit, necessitating sufficient barrier thickness.

Side effects on surrounding parts

Side effects on surrounding parts
AffectsEffect
Respiratory tractTobacco smoke contaminated with PFA dust converts benign polymer dust into toxic gaseous fluorinated breakdown products.

Handling and storage

  • Provide local exhaust ventilation during hot melt processing to remove all liberated vapors and fumes from the work area.
  • Extrusion barrels and tooling in contact with molten resin at 390 °C must be fabricated from corrosion-resistant alloys such as Monel, Inconel, or Hastelloy.

Mitigations

  • Maintain processing temperatures strictly below decomposition limits and use positive pressure air respirators if ventilation is inadequate.

Supply and geography

How common the raw materials are and where they come from.

Fluorspar (CaF2), the mineral feedstock for fluorine chemistry

Fluorspar is the primary mineral source of hydrogen fluoride used to synthesize fluoropolymers; USGS reports that the United States is 100% net import reliant for fluorspar.

Top producers (2025)
China 60%, Mexico 15%, Mongolia 15%, South Africa 4.1%
Critical mineral lists
US: listed