{
  "spore": "profile",
  "id": "af",
  "spore_version": "0.2",
  "family": "fluoropolymers",
  "name": "Amorphous fluoropolymer (Teflon AF)",
  "abbreviation": "AF",
  "role": "clear, amorphous fluoroplastic coating and optical-cladding polymer",
  "category": "polymers",
  "type": "fluoropolymers",
  "summary": "Amorphous fluoropolymer, sold by Chemours as Teflon AF, is a glassy fluoroplastic that dissolves in selected perfluorinated solvents, so it can be spun, sprayed or dipped into thin films. On the NASA MISSE 2 PEACE flight outside the ISS it eroded under atomic oxygen at 1.98e-25 cm3/atom, about the same as FEP (2.00e-25 cm3/atom) and a little more than PTFE (1.42e-25 cm3/atom), and about fifteen times less than Kapton H (3.00e-24 cm3/atom). Chemours gives a glass transition of 160 degC for its 1600 grade and a refractive index of 1.31.",
  "best_for": "Thin, low-index, optically clear and hydrophobic fluoropolymer coatings and claddings that must survive atomic oxygen in low Earth orbit",
  "weakest_at": "Strength and stiffness at high temperature: tensile strength falls from 26.9 MPa at 23 degC to 7.7 MPa at 220 degC, and the material decomposes above 360 degC",
  "identity": {
    "formula": "Amorphous fluoropolymer; NASA repeat unit C19O6F32 for Teflon AF 1601",
    "cas": "",
    "designations": [],
    "source": "nasa-2008",
    "where": "Table V (repeat-unit atom counts for AF: C19 O6 F32, 57 atoms in total); formula and molar mass 932.1414 from the AF row of the composition table in the same report"
  },
  "tags": {
    "environments": [
      "low-earth-orbit"
    ],
    "stresses": [
      "atomic-oxygen",
      "thermal-cycling"
    ],
    "applications": [
      "optics-and-cameras",
      "electronics-and-chips"
    ]
  },
  "properties": [
    {
      "benchmark": "atomic_oxygen_erosion_yield",
      "label": "Atomic oxygen erosion yield (MISSE 2 PEACE, ISS)",
      "value": 1.98e-25,
      "bound": "exact",
      "unit": "cm3/atom",
      "scope": "material",
      "conditions": {
        "grade_flown": "Teflon AF 1601",
        "exposure": "outside the ISS, MISSE 2 PEACE tray E5",
        "atomic_oxygen_fluence": "8.43e21 atoms/cm2",
        "solar_exposure": "6,300 ESH",
        "uncertainty": "plus or minus 0.05E-25 cm3/atom (NASA/TM-2010-216903, Table 6)"
      },
      "method": "Mass loss measured after flight, divided by density, area and fluence, as tabulated by NASA",
      "status": "flight",
      "source": "nasa-2006",
      "where": "Table 4, row 2-E5-45 (Amorphous Fluoropolymer, AF, erosion yield column)",
      "source_detail": {
        "title": "MISSE PEACE Polymers Atomic Oxygen Erosion Results (NASA/TM-2006-214482)",
        "id": "NASA/TM-2006-214482 (de Groh and Banks, November 2006)",
        "url": "https://ntrs.nasa.gov/api/citations/20070002707/downloads/20070002707.pdf",
        "year": 2006,
        "kind": "report",
        "license": "NASA technical report (public)"
      }
    },
    {
      "benchmark": "density",
      "label": "Density (MISSE 2 PEACE sample)",
      "value": 2.1463,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "grade_flown": "Teflon AF 1601"
      },
      "method": "Density gradient column testing as described by NASA",
      "status": "ground",
      "source": "nasa-2006",
      "where": "Table 4, row 2-E5-45, density column",
      "source_detail": {
        "title": "MISSE PEACE Polymers Atomic Oxygen Erosion Results (NASA/TM-2006-214482)",
        "id": "NASA/TM-2006-214482 (de Groh and Banks, November 2006)",
        "url": "https://ntrs.nasa.gov/api/citations/20070002707/downloads/20070002707.pdf",
        "year": 2006,
        "kind": "report",
        "license": "NASA technical report (public)"
      }
    },
    {
      "benchmark": "ash_mass_fraction",
      "label": "Ash content (mass fraction of polymer that is ash)",
      "value": 0.0358,
      "bound": "exact",
      "unit": "mass fraction",
      "scope": "material",
      "conditions": {
        "grade_flown": "Teflon AF 1601"
      },
      "method": "Fractional ash content measured for the MISSE 2 PEACE polymers",
      "status": "ground",
      "source": "nasa-2008",
      "where": "Table II, AF row (mass fraction of polymer that is ash, Na)",
      "source_detail": {
        "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit",
        "id": "NASA/TM-2008-215490 (Banks, Backus and de Groh, December 2008)",
        "url": "https://ntrs.nasa.gov/citations/20090011780",
        "year": 2008,
        "kind": "report",
        "license": "NASA technical report (public)"
      }
    },
    {
      "benchmark": "specific_gravity",
      "label": "Specific gravity (grade 1600)",
      "value": 1.78,
      "bound": "exact",
      "unit": "none",
      "scope": "material",
      "conditions": {
        "grade": "1600"
      },
      "method": "ASTM D792, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Other section, Specific Gravity row, 1600 column",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "glass_transition_temperature",
      "label": "Glass transition temperature (grade 1600)",
      "value": 160,
      "bound": "exact",
      "unit": "degC",
      "scope": "material",
      "conditions": {
        "grade": "1600",
        "tolerance": "plus or minus 5 degC as printed (320 degF)"
      },
      "method": "ASTM D3418, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Other section, Tg row, 1600 column",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "refractive_index",
      "label": "Refractive index (grade 1600)",
      "value": 1.31,
      "bound": "exact",
      "unit": "unitless",
      "scope": "material",
      "conditions": {
        "grade": "1600"
      },
      "method": "ASTM D542, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Optical section, Refractive Index row, 1600 column",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "dielectric_constant",
      "label": "Dielectric constant (grade 1600)",
      "value": 1.93,
      "bound": "exact",
      "unit": "unitless",
      "scope": "material",
      "conditions": {
        "grade": "1600"
      },
      "method": "ASTM D150, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Electrical section, Dielectric Constant row, 1600 column",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "dielectric_strength",
      "label": "Dielectric strength (grade 1600)",
      "value": 2.1,
      "bound": "exact",
      "unit": "kV/0.1 mm",
      "scope": "material",
      "conditions": {
        "grade": "1600"
      },
      "method": "ASTM D149, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Electrical section, Dielectric Strength row, 1600 column",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "dissipation_factor",
      "label": "Dissipation factor (grade 1600)",
      "value": 0.0001,
      "value_high": 0.0002,
      "bound": "exact",
      "unit": "unitless",
      "scope": "material",
      "conditions": {
        "grade": "1600"
      },
      "method": "ASTM D150, as printed as a range by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Electrical section, Dissipation Factor row, 1600 column",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "optical_transmission",
      "label": "Optical transmission (grade 1600)",
      "value": 95,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "grade": "1600",
        "note": "printed as greater than 95 percent"
      },
      "method": "ASTM D1003, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Optical section, Optical Transmission row",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "water_contact_angle",
      "label": "Contact angle with water (grade 1600)",
      "value": 104,
      "bound": "exact",
      "unit": "degrees",
      "scope": "material",
      "conditions": {
        "grade": "1600"
      },
      "method": "ASTM D570, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Chemical section, Contact Angle with Water row, 1600 column",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "critical_surface_energy",
      "label": "Critical surface energy (grade 1600)",
      "value": 15.7,
      "bound": "exact",
      "unit": "dynes/cm",
      "scope": "material",
      "conditions": {
        "grade": "1600"
      },
      "method": "As printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Chemical section, Critical Surface Energy row, 1600 column",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "moisture_absorption",
      "label": "Water absorption (grade 1600)",
      "value": 0.01,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "grade": "1600",
        "note": "printed as less than 0.01 percent"
      },
      "method": "As printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Chemical section, Water Absorption row, 1600 column",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Yield strength at 23 degC (grade 1600)",
      "value": 27.4,
      "value_high": 28.4,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "grade": "1600",
        "temperature": "23 degC (73 degF)",
        "note": "printed as 27.4 plus or minus 1.0 MPa"
      },
      "method": "As printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Mechanical section, Yield Strength row, 23 degC line",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength at 23 degC (grade 1600)",
      "value": 26.9,
      "value_high": 28.4,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "grade": "1600",
        "temperature": "23 degC (73 degF)",
        "note": "printed as 26.9 plus or minus 1.5 MPa"
      },
      "method": "ASTM D638, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Mechanical section, Tensile Strength row, 23 degC line",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength at 220 degC (grade 1600)",
      "value": 7.7,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "grade": "1600",
        "temperature": "220 degC (428 degF)",
        "note": "printed as 7.7 plus or minus 6.1 MPa"
      },
      "method": "ASTM D638, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Mechanical section, Tensile Strength row, 220 degC line",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Elongation at break at 23 degC (grade 1600)",
      "value": 17.1,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "grade": "1600",
        "temperature": "23 degC (73 degF)",
        "note": "printed as 17.1 plus or minus 5.0 percent"
      },
      "method": "ASTM D638, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Mechanical section, Elongation at Break row, 23 degC line",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Tensile modulus (grade 1600)",
      "value": 1.6,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "grade": "1600"
      },
      "method": "ASTM D638, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Mechanical section, Tensile Modulus row, 1600 column",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "flexural_modulus",
      "label": "Flexural modulus at 23 degC (grade 1600)",
      "value": 1.8,
      "value_high": 1.9,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "grade": "1600",
        "temperature": "23 degC (73 degF)",
        "note": "printed as 1.8 plus or minus 0.1 GPa"
      },
      "method": "ASTM D790, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Mechanical section, Flexural Modulus row, 23 degC line",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "heat_deflection_temperature",
      "label": "Deflection temperature at 66 psi (grade 1600)",
      "value": 156,
      "bound": "exact",
      "unit": "degC",
      "scope": "material",
      "conditions": {
        "grade": "1600",
        "load": "66 psi"
      },
      "method": "ASTM D648, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Mechanical section, Deflection Temperature row, 66 psi line",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "volume_cte",
      "label": "Volume coefficient of thermal expansion (grade 1600)",
      "value": 260,
      "bound": "exact",
      "unit": "ppm/degC",
      "scope": "material",
      "conditions": {
        "grade": "1600"
      },
      "method": "ASTM E831, as printed by the manufacturer",
      "status": "ground",
      "source": "chemours-af",
      "where": "Typical Property Data table, Other section, Volume Coefficient of Thermal Expansion row",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    },
    {
      "benchmark": "decomposition_onset_temperature",
      "label": "Onset of decomposition",
      "value": 360,
      "bound": "exact",
      "unit": "degC",
      "scope": "material",
      "conditions": {
        "note": "The polymer begins to decompose above 360 degC (680 degF)"
      },
      "method": "Manufacturer processing guidance",
      "status": "ground",
      "source": "chemours-af",
      "where": "Processing section, first paragraph (molding temperatures and decomposition warning)",
      "source_detail": {
        "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
        "id": "Chemours Teflon AF product information",
        "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
        "kind": "datasheet",
        "license": "Manufacturer product information (cited, not reproduced)"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Low Earth orbit, atomic oxygen (MISSE 2 PEACE, ISS)",
      "headline": "Erodes at about the same rate as FEP and a little faster than PTFE, and about fifteen times slower than Kapton H.",
      "effect": "On the MISSE 2 PEACE tray, AF eroded at 1.98e-25 cm3/atom. In the same table FEP eroded at 2.00e-25 cm3/atom, PTFE at 1.42e-25 cm3/atom, and Kapton H at 3.00e-24 cm3/atom.",
      "rating": "unknown",
      "source": "nasa-2006",
      "where": "Table 4 (rows 2-E5-42, 2-E5-43, 2-E5-45 and 2-E5-30); NASA/TM-2008-215490 introduction"
    },
    {
      "environment": "Thermal cycling on an ISS base plate",
      "headline": "The flight tray saw a nominal base-plate range of +40 degC to -30 degC.",
      "effect": "The MISSE 2 base-plate thermal cycling range was nominally between +40 degC and -30 degC, with occasional short excursions. The fetched pages report no AF-specific damage from this cycling, so the effect is not known from these sources.",
      "rating": "unknown",
      "source": "nasa-2006",
      "where": "Section 2 (MISSE 2 flight description), thermal cycling paragraph"
    },
    {
      "environment": "Heating during processing or use",
      "headline": "The polymer begins to decompose above 360 degC, and its tensile strength is much lower at 220 degC.",
      "effect": "Chemours says processing above 360 degC should be avoided. At 220 degC the grade 1600 tensile strength is 7.7 MPa, against 26.9 MPa at 23 degC.",
      "rating": "unknown",
      "source": "chemours-af",
      "where": "Processing section and Mechanical section of the Typical Property Data table"
    },
    {
      "environment": "Water and humid air",
      "headline": "Takes up very little water and is strongly water-repellent.",
      "effect": "Water absorption is printed as less than 0.01 percent, and the contact angle with water is 104 degrees for grade 1600. No corrosion or hydrolysis data for AF were found in the fetched pages.",
      "rating": "unknown",
      "source": "chemours-af",
      "where": "Chemical section of the Typical Property Data table"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "Chemours says the resin may contain parts per million of residual hexafluoroacetone (HFA), which is readily absorbed through the skin. Residual gases including HF, COF2, CO and HFA diffuse from the resin even at room temperature and may be harmful.",
        "ghs": [],
        "source": "chemours-af",
        "where": "Handling Practices paragraph"
      },
      {
        "text": "Chemours warns that vapors can be liberated from Teflon AF that may be hazardous if inhaled.",
        "ghs": [],
        "source": "chemours-af",
        "where": "Safety Precautions box"
      },
      {
        "text": "PubChem's hexafluoroacetone record lists H330 (98.9%) Fatal if inhaled, H310 (25.1%) Fatal in contact with skin, and H314 (73.8%) Causes severe skin burns and eye damage, with signal word Danger.",
        "ghs": [
          "H330",
          "H310",
          "H314"
        ],
        "source": "pubchem-hfa",
        "where": "GHS Classification, CID 12695"
      },
      {
        "text": "Hydrogen fluoride is named among the residual gases. PubChem's hydrofluoric acid record lists H330 Fatal if inhaled and H314 Causes severe skin burns and eye damage.",
        "ghs": [
          "H330",
          "H314"
        ],
        "source": "pubchem-hf",
        "where": "GHS Classification, CID 14917 (Hydrofluoric Acid)"
      },
      {
        "text": "Chemours cautions against medical use involving permanent implantation in the human body or contact with bodily fluids or tissues, unless covered by a written contract.",
        "ghs": [],
        "source": "chemours-af",
        "where": "Caution note at the end of the product information"
      }
    ],
    "failure_risks": [
      {
        "mode": "Atomic oxygen erosion removes material at 1.98e-25 cm3/atom in low…",
        "consequence": "Atomic oxygen erosion removes material at 1.98e-25 cm3/atom in low Earth orbit. The MISSE 2 film was 2 mils thick, so the film thins with fluence.",
        "source": "nasa-2006",
        "where": "Table 4, row 2-E5-45; thickness from NASA/TM-2010-216903, Table 1"
      },
      {
        "mode": "Strength and stiffness fall at high temperature",
        "consequence": "Strength and stiffness fall at high temperature. Grade 1600 tensile strength is 7.7 MPa at 220 degC against 26.9 MPa at 23 degC.",
        "source": "chemours-af",
        "where": "Mechanical section of the Typical Property Data table"
      },
      {
        "mode": "Processing above 360 degC decomposes the polymer",
        "consequence": "Processing above 360 degC decomposes the polymer.",
        "source": "chemours-af",
        "where": "Processing section"
      }
    ],
    "side_effects": [],
    "handling": [
      {
        "text": "Before using Teflon AF, read the Safety Data Sheet and the Guide to the Safe Handling of Fluoropolymer Resins, as Chemours instructs.",
        "source": "chemours-af",
        "where": "Safety Precautions box"
      },
      {
        "text": "Avoid skin contact with the resin during processing, and wear protective gloves when handling it in manufacturing operations.",
        "source": "chemours-af",
        "where": "Handling Practices paragraph"
      },
      {
        "text": "Keep processing below 360 degC and use corrosion-resistant tooling, as recommended for Teflon FEP and PFA.",
        "source": "chemours-af",
        "where": "Processing section"
      }
    ],
    "mitigations": [
      {
        "text": "Keep processing temperatures below the 360 degC decomposition onset, and use corrosion-resistant tooling.",
        "source": "chemours-af",
        "where": "Processing section"
      }
    ]
  },
  "uses": [
    {
      "application": "optics-and-cameras",
      "device": "Low-index optical cladding and anti-reflective coatings",
      "example": "Chemours lists its use in fiber optics as a low refractive index, high temperature cladding material over silica, methacrylates, and polycarbonates.",
      "source": "chemours-af",
      "where": "Chemical Applications list, Optical section of the product information"
    },
    {
      "application": "electronics-and-chips",
      "device": "Hydrophobic dielectric layer in electrowetting devices",
      "example": "The paper made 800 nm thick amorphous fluoropolymer films by screen printing Teflon AF 1600 solution (Chemours) onto substrates for its charge-trapping and electrowetting study.",
      "source": "arxiv-electrowetting",
      "where": "Section on sample preparation (Methods)"
    }
  ],
  "supply": [
    {
      "subject": "Fluorine feedstock: fluorspar (calcium fluoride, CaF2)",
      "abundance": "USGS estimates global mine production decreased by 1 percent to 10 million tons in 2025. The world reserves total is printed as 330,000 in the USGS table, with no unit printed beside it.",
      "producers": [
        {
          "country": "Mexico",
          "share_percent": 64
        }
      ],
      "critical_lists": [],
      "recycling": "USGS notes that synthetic fluorspar may be produced from neutralization of waste in uranium enrichment, petroleum alkylation and other processes.",
      "substitutes": [
        "USGS lists fluorspar substitutes for some uses, such as AlF3 and HF production."
      ],
      "source": "usgs-fluorspar-2026",
      "where": "Mineral Commodity Summaries 2026, Fluorspar: Import Sources (2021-24), World Mine Production and Reserves tables, Recycling and Substitutes paragraphs"
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "NASA/TM-2008-215490: Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit",
      "type": "report",
      "url": "https://ntrs.nasa.gov/citations/20090011780",
      "year": 2008
    },
    {
      "title": "NASA/TM-2006-214482: MISSE PEACE Polymers Atomic Oxygen Erosion Results",
      "type": "report",
      "url": "https://ntrs.nasa.gov/api/citations/20070002707/downloads/20070002707.pdf",
      "year": 2006
    },
    {
      "title": "NASA/TM-2010-216903: MISSE 2 PEACE Polymers Atomic Oxygen Erosion Yield Error Analysis",
      "type": "report",
      "url": "https://ntrs.nasa.gov/api/citations/20100040422/downloads/20100040422.pdf",
      "year": 2010
    },
    {
      "title": "Chemours Teflon AF Amorphous Fluoroplastic Resins product information",
      "type": "datasheet",
      "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf"
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026: Fluorspar",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-fluorspar.pdf",
      "year": 2026
    },
    {
      "title": "PubChem: Hexafluoroacetone (CID 12695), GHS classification",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/12695/JSON"
    },
    {
      "title": "PubChem: Hydrofluoric Acid (CID 14917), GHS classification",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/14917/JSON"
    },
    {
      "title": "Electrically controlled localized charge trapping at amorphous fluoropolymer-electrolyte interfaces (arXiv:1909.09424)",
      "type": "paper",
      "url": "https://arxiv.org/pdf/1909.09424",
      "year": 2019
    }
  ],
  "gaps": [
    "No ionizing-radiation, ultraviolet, outgassing or thermal-vacuum result for AF was found in the fetched pages.",
    "No Teflon AF safety data sheet was reached. Hazards come from the Chemours product sheet and PubChem records for hexafluoroacetone and hydrofluoric acid.",
    "The MISSE 2 PEACE flight dates were not re-read in this run, so they are not stated in the file.",
    "The NASA flight grade is Teflon AF 1601, but the Chemours datasheet values are for grade 1600 (and 2400 was not used). Grade differences are not resolved.",
    "No production or capacity figures for Teflon AF itself were found. The supply section covers fluorspar only, the mineral feedstock for fluorine chemistry.",
    "USGS does not list fluorspar as a 2025 critical mineral in the fetched text, so no critical-list entry is given.",
    "Element atomic weights were not read in this run, so the recipe parts give atom counts only.",
    "Non-canonical benchmark names used: atomic_oxygen_erosion_yield, ash_mass_fraction, water_contact_angle, critical_surface_energy, volume_cte, decomposition_onset_temperature, optical_transmission.",
    "Side effects are not stated for AF in any fetched source."
  ],
  "story": {
    "why": "AF is a clear, amorphous fluoropolymer with a low refractive index and a low dielectric constant. On the MISSE 2 PEACE flight outside the ISS it eroded at 1.98e-25 cm3/atom, which puts it in the low-erosion group of fluoropolymers. It is a candidate where a thin, optically clear or hydrophobic coating must survive atomic oxygen in low Earth orbit.",
    "uses": [
      {
        "where": "Use",
        "line": "Optical cladding and anti-reflective coatings, where its refractive index of 1.31 is the reason it is used (Chemours)."
      },
      {
        "where": "Use",
        "line": "Hydrophobic dielectric layers in electrowetting devices, as used in the arXiv paper with Teflon AF 1600 films."
      }
    ],
    "can_do": [
      {
        "label": "Erosion in low Earth orbit",
        "line": "The MISSE 2 PEACE measurement gives 1.98e-25 cm3/atom after an atomic oxygen fluence of 8.43e21 atoms/cm2 and about 6,300 equivalent sun hours.",
        "benchmark": "atomic_oxygen_erosion_yield",
        "scope": "material"
      },
      {
        "label": "Optics",
        "line": "The grade 1600 refractive index is 1.31, and the optical transmission is printed as greater than 95 percent.",
        "benchmark": "refractive_index",
        "scope": "material"
      },
      {
        "label": "Heat",
        "line": "The grade 1600 glass transition is 160 degC, and the deflection temperature at 66 psi is 156 degC.",
        "benchmark": "glass_transition_temperature",
        "scope": "material"
      }
    ],
    "compare": "AF is a low-erosion fluoropolymer. Among the MISSE 2 PEACE polymers it eroded about as much as FEP and somewhat more than PTFE, but far less than Kapton H, PEEK or polyethylene in the same MISSE 2 table. Its room-temperature strength is low. The compare rows show the three numbers that most often decide between it and the alternatives.",
    "compare_rows": [
      {
        "label": "Erosion under atomic oxygen",
        "benchmark": "atomic_oxygen_erosion_yield",
        "scope": "material"
      },
      {
        "label": "Glass transition",
        "benchmark": "glass_transition_temperature",
        "scope": "material"
      },
      {
        "label": "Refractive index",
        "benchmark": "refractive_index",
        "scope": "material"
      }
    ],
    "handling": [
      "Read the Chemours safety data sheet and the Guide to the Safe Handling of Fluoropolymer Resins before use. Keep processing below 360 degC, use protective gloves, and avoid skin contact with the resin during processing, because residual HFA is absorbed through the skin."
    ],
    "good_for": [
      "Thin, optically clear, low-index or hydrophobic coatings and claddings that must survive atomic oxygen in low Earth orbit with less erosion than most hydrocarbon or polyimide films."
    ],
    "watch_out": [
      "Do not heat it above 360 degC, where it decomposes. Its strength is low at room temperature (26.9 MPa) and drops to 7.7 MPa at 220 degC. Residual HFA and other gases can be harmful."
    ],
    "verdict": "AF erodes slowly in low Earth orbit and is a sound choice for thin optical and hydrophobic layers. It is soft and weak, so it is a coating, not a structural material.",
    "recipe": {
      "line": "Amorphous fluoropolymer is a fluorine-rich polymer. NASA's composition table gives the Teflon AF 1601 repeat unit as C19O6F32, with 57 atoms per unit and a molar mass of 932.1414. Chemours says it is dissolved in certain perfluorinated solvents and then spun, sprayed or dipped into thin films.",
      "parts": [
        {
          "name": "Carbon",
          "symbol": "C",
          "role": "Backbone and side-group carbon. With fluorine it forms the perfluorinated, low-polarizability structure behind the low refractive index and dielectric constant."
        },
        {
          "name": "Oxygen",
          "symbol": "O",
          "role": "Ether oxygens in the ring structure. NASA counts these in its erosion model, since atomic oxygen can react with them."
        },
        {
          "name": "Fluorine",
          "symbol": "F",
          "role": "Most of the repeat unit by count. Fluorine gives the chemical resistance, low surface energy and low water absorption that Chemours reports."
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "Chemours and PubChem name hexafluoroacetone, hydrogen fluoride and other residual gases as the hazard. The fetched sources do not describe the hazard of the solid polymer itself.",
        "points": [
          {
            "label": "Residual gases",
            "line": "Chemours says residual gases, including HF, COF2, CO and HFA, diffuse from the resin even at room temperature and may be harmful."
          },
          {
            "label": "Medical use",
            "line": "Chemours does not allow permanent implantation or contact with bodily fluids unless covered by a written contract."
          }
        ],
        "level": 1,
        "verdict": "Hazards come from residual gases and vapours, not from the…"
      }
    ]
  },
  "updated": "2026-10-20",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 22,
    "unreachable": 0,
    "caveats": 1,
    "note": "Written by an AI assistant on 2026-10-20 from pages fetched in this run: NASA/TM-2006-214482 Table 4, NASA/TM-2008-215490 Tables I, II and V, NASA/TM-2010-216903 Tables 1 and 6, the Chemours product information PDF, USGS MCS 2026 fluorspar, PubChem CID 12695 and 14917, and arXiv:1909.09424. Flight dates from the passport were not re-read."
  },
  "sources": {
    "nasa-2006": {
      "title": "MISSE PEACE Polymers Atomic Oxygen Erosion Results (NASA/TM-2006-214482)",
      "id": "NASA/TM-2006-214482 (de Groh and Banks, November 2006)",
      "url": "https://ntrs.nasa.gov/api/citations/20070002707/downloads/20070002707.pdf",
      "year": 2006,
      "kind": "report",
      "license": "NASA technical report (public)"
    },
    "nasa-2008": {
      "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit",
      "id": "NASA/TM-2008-215490 (Banks, Backus and de Groh, December 2008)",
      "url": "https://ntrs.nasa.gov/citations/20090011780",
      "year": 2008,
      "kind": "report",
      "license": "NASA technical report (public)"
    },
    "nasa-2010": {
      "title": "MISSE 2 PEACE Polymers Experiment Atomic Oxygen Erosion Yield Error Analysis",
      "id": "NASA/TM-2010-216903",
      "url": "https://ntrs.nasa.gov/api/citations/20100040422/downloads/20100040422.pdf",
      "year": 2010,
      "kind": "report",
      "license": "NASA technical report (public)"
    },
    "chemours-af": {
      "title": "Teflon AF Amorphous Fluoroplastic Resins product information",
      "id": "Chemours Teflon AF product information",
      "url": "https://www.teflon.com/en/-/media/files/teflon/teflon-af-product-info.pdf",
      "kind": "datasheet",
      "license": "Manufacturer product information (cited, not reproduced)"
    },
    "usgs-fluorspar-2026": {
      "title": "Mineral Commodity Summaries 2026: Fluorspar",
      "id": "USGS Mineral Commodity Summaries 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-fluorspar.pdf",
      "year": 2026,
      "kind": "report",
      "license": "US government work (public domain)"
    },
    "pubchem-hfa": {
      "title": "PubChem: Hexafluoroacetone (CID 12695), GHS classification",
      "id": "PubChem CID 12695",
      "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/12695/JSON",
      "kind": "database",
      "license": "PubChem (NIH, public)"
    },
    "pubchem-hf": {
      "title": "PubChem: Hydrofluoric Acid (CID 14917), GHS classification",
      "id": "PubChem CID 14917",
      "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/14917/JSON",
      "kind": "database",
      "license": "PubChem (NIH, public)"
    },
    "arxiv-electrowetting": {
      "title": "Electrically controlled localized charge trapping at amorphous fluoropolymer-electrolyte interfaces",
      "id": "arXiv:1909.09424 (Wu, Dey, Siretanu, van den Ende, Shui, Zhou, Mugele)",
      "url": "https://arxiv.org/pdf/1909.09424",
      "year": 2019,
      "kind": "paper",
      "license": "arXiv preprint (cited)"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/af/"
}