{
  "spore": "profile",
  "id": "ectfe-halar",
  "spore_version": "0.2",
  "family": "fluoropolymers",
  "name": "Ethylene-chlorotrifluoroethylene",
  "abbreviation": "ECTFE (Halar)",
  "role": "tough, chemically resistant semi-crystalline fluoropolymer for linings, pipes and cable jackets",
  "category": "polymers",
  "type": "fluoropolymers",
  "summary": "ECTFE (Halar, from Solvay) is an alternating copolymer of ethylene and chlorotrifluoroethylene. It is tougher than PTFE, has a continuous service range of -76 °C to +150 °C and resists most acids, alkalis and solvents. On the MISSE 2 flight it eroded under atomic oxygen at 1.79e-24 cm3/atom, about the same as Kapton H and far worse than PTFE. Its weak points are atomic oxygen compared with PTFE, and overheating above about 350 °C, which releases hydrogen fluoride.\n",
  "best_for": "Corrosion-resistant linings, pipes and tanks, and wire or cable jacketing that must survive acids and solvents and still be tough",
  "weakest_at": "Atomic oxygen in low Earth orbit (far more than PTFE on the MISSE 2 flight) and overheating, which gives toxic and corrosive fumes including hydrogen fluoride",
  "identity": {
    "formula": "(C2H4)n(C2ClF3)n, alternating copolymer; repeat unit C4H4ClF3",
    "cas": "25101-45-5",
    "designations": [],
    "source": "wiki-ectfe",
    "where": "Infobox (CAS 25101-45-5, alternating copolymer of ethylene and chlorotrifluoroethylene); PubChem record 25101-45-5 gives the formula (C2H4.C2ClF3)x; repeat unit C4H4ClF3 from the NASA MISSE 2 table"
  },
  "tags": {
    "environments": [
      "low-earth-orbit"
    ],
    "stresses": [
      "atomic-oxygen",
      "uv"
    ],
    "applications": [
      "electronics-and-chips",
      "cryogenic-fuel"
    ]
  },
  "properties": [
    {
      "benchmark": "atomic_oxygen_erosion_yield",
      "label": "Atomic oxygen erosion yield (MISSE 2 flight)",
      "value": 1.79e-24,
      "bound": "exact",
      "unit": "cm3/atom",
      "scope": "material",
      "conditions": {
        "environment": "low Earth orbit, ISS, MISSE 2 PEACE Polymers tray",
        "fluence": "8.43e21 atoms/cm2",
        "duration": "3.95 years"
      },
      "method": "Flight measurement reported in a NASA technical memorandum predictive-tool table",
      "status": "flight",
      "source": "banks2008",
      "where": "Table I, row Ethylene-chlorotrifluoroethylene, ECTFE (Halar)",
      "source_detail": {
        "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit",
        "id": "NASA/TM-2008-215490, NTRS 20090011780 (Banks, de Groh, Backus; December 2008)",
        "url": "https://ntrs.nasa.gov/citations/20090011780",
        "year": 2008,
        "kind": "report",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "density",
      "label": "Specific gravity (D792)",
      "value": 1.68,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "test_standard": "ASTM D792",
        "form": "typical value, Halar ECTFE"
      },
      "method": "Typical value printed in a materials data sheet",
      "status": "ground",
      "source": "wk-halar",
      "where": "Typical properties table, PHYSICAL, Density (g/cm3) row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "density",
      "label": "Density range (Halar 901S SDS)",
      "value": 1.65,
      "value_high": 1.71,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "form": "Halar 901S resin"
      },
      "method": "Range printed in a manufacturer safety data sheet, Section 9",
      "status": "ground",
      "source": "gfps-sds",
      "where": "Section 9, Density row (Revision 08.09.2016)",
      "source_detail": {
        "title": "Halar 901S Safety Data Sheet (GFPS)",
        "id": "Revision 08.09.2016, version 2.04",
        "url": "https://www.gfps.com/content/dam/gfps/us/products/piping-systems/sygef-ectfe/Extrusion%20-%20Halar%20901S-SDS_GB-EN-2.04.pdf",
        "year": 2016,
        "kind": "datasheet",
        "license": "manufacturer document, linked not reproduced"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point",
      "value": 238,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "printed": "460 °F",
        "test_standard": "ASTM D3418"
      },
      "method": "Typical value printed in a materials data sheet",
      "status": "ground",
      "note": "The Halar 901S safety data sheet gives a melting range of 230 to 242 °C.",
      "source": "wk-halar",
      "where": "Thermal table, Melting Temp (°F / °C) row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "heat_deflection_temperature",
      "label": "Heat deflection temperature at 264 psi",
      "value": 115,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "pressure": "264 psi",
        "test_standard": "ASTM D648",
        "printed": "240 °F"
      },
      "method": "Typical value printed in a materials data sheet",
      "status": "ground",
      "source": "wk-halar",
      "where": "Thermal table, Heat Deflection Temp row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "max_service_temp",
      "label": "Maximum operating temperature (data sheet)",
      "value": 149,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "printed": "300 °F",
        "basis": "typical performance in many applications"
      },
      "method": "Typical value printed in a materials data sheet",
      "status": "ground",
      "source": "wk-halar",
      "where": "Thermal table, Max Operating Temp row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "max_service_temp",
      "label": "Upper service temperature (rod stock)",
      "value": 150,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "form": "Halar 901 rod, machined stock",
        "printed": "302 °F"
      },
      "method": "Printed value on a supplier product sheet",
      "status": "ground",
      "source": "pexco-ectfe",
      "where": "Specifications box, Temperature line",
      "source_detail": {
        "title": "Pexco ECTFE Rod product sheet (Halar 901 resin)",
        "id": "Pexco product sheet, February 2026",
        "url": "https://www.pexco.com/wp-content/uploads/2026/02/Pexco-ECTFE-Rod_productsheet_Feb2026.pdf",
        "year": 2026,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "min_service_temp",
      "label": "Continuous usage lower limit",
      "value": -76,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "basis": "continuous usage temperature range (-105 °F to +300 °F as printed)"
      },
      "method": "Range stated in a reference encyclopedia article, which cites the Polymer Handbook and manufacturer data",
      "status": "ground",
      "source": "wiki-ectfe",
      "where": "Physical and chemical properties section, first paragraph",
      "source_detail": {
        "title": "ECTFE (Wikipedia)",
        "id": "Wikipedia article, read in this run",
        "url": "https://en.wikipedia.org/wiki/ECTFE",
        "year": 2026,
        "kind": "web",
        "license": "CC BY-SA 4.0"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength (data sheet)",
      "value": 7000,
      "bound": "exact",
      "unit": "psi",
      "scope": "material",
      "conditions": {
        "test_standard": "ASTM D638",
        "form": "typical value, Halar ECTFE"
      },
      "method": "Typical value printed in a materials data sheet",
      "status": "ground",
      "source": "wk-halar",
      "where": "Mechanical table, Tensile Strength row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength (rod stock)",
      "value": 8000,
      "bound": "exact",
      "unit": "psi",
      "scope": "material",
      "conditions": {
        "test_standard": "ASTM D638",
        "form": "Halar 901 rod"
      },
      "method": "Printed value on a supplier product sheet",
      "status": "ground",
      "source": "pexco-ectfe",
      "where": "Tensile Strength row",
      "source_detail": {
        "title": "Pexco ECTFE Rod product sheet (Halar 901 resin)",
        "id": "Pexco product sheet, February 2026",
        "url": "https://www.pexco.com/wp-content/uploads/2026/02/Pexco-ECTFE-Rod_productsheet_Feb2026.pdf",
        "year": 2026,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Elongation at break (data sheet)",
      "value": 200,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "test_standard": "ASTM D638",
        "form": "typical value, Halar ECTFE"
      },
      "method": "Typical value printed in a materials data sheet",
      "status": "ground",
      "source": "wk-halar",
      "where": "Mechanical table, Tensile Elongation at Break row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Elongation at break (rod stock)",
      "value": 250,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "test_standard": "ASTM D638",
        "form": "Halar 901 rod"
      },
      "method": "Printed value on a supplier product sheet",
      "status": "ground",
      "source": "pexco-ectfe",
      "where": "Elongation at Break row",
      "source_detail": {
        "title": "Pexco ECTFE Rod product sheet (Halar 901 resin)",
        "id": "Pexco product sheet, February 2026",
        "url": "https://www.pexco.com/wp-content/uploads/2026/02/Pexco-ECTFE-Rod_productsheet_Feb2026.pdf",
        "year": 2026,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Tensile modulus",
      "value": 240000,
      "bound": "exact",
      "unit": "psi",
      "scope": "material",
      "conditions": {
        "test_standard": "ASTM D638",
        "form": "typical value, Halar ECTFE"
      },
      "method": "Typical value printed in a materials data sheet",
      "status": "ground",
      "source": "wk-halar",
      "where": "Mechanical table, Tensile Modulus row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "dielectric_constant",
      "label": "Dielectric constant at 1 MHz",
      "value": 2.5,
      "bound": "exact",
      "unit": "none",
      "scope": "material",
      "conditions": {
        "test_standard": "ASTM D150",
        "frequency": "1 MHz",
        "temperature": "23 °C"
      },
      "method": "Typical value printed in a materials data sheet",
      "status": "ground",
      "source": "wk-halar",
      "where": "Electrical table, Dielectric Constant at 1 MHz row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "dielectric_strength",
      "label": "Dielectric strength (short time)",
      "value": 500,
      "bound": "exact",
      "unit": "V/mil",
      "scope": "material",
      "conditions": {
        "test_standard": "ASTM D149",
        "thickness": "1/8 inch"
      },
      "method": "Typical value printed in a materials data sheet",
      "status": "ground",
      "source": "wk-halar",
      "where": "Electrical table, Dielectric Strength row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "electrical_resistivity",
      "label": "Volume resistivity",
      "value": 1000000000000000,
      "bound": "exact",
      "unit": "ohm-cm",
      "scope": "material",
      "conditions": {
        "humidity": "50% RH",
        "printed": "1015 (exponent printed as superscript)"
      },
      "method": "Typical value printed in a materials data sheet",
      "status": "ground",
      "source": "wk-halar",
      "where": "Electrical table, Volume Resistivity row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "moisture_absorption",
      "label": "Water absorption, 24 hours",
      "value": 0.1,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "test_standard": "ASTM D570",
        "time": "24 hours",
        "printed": "< 0.1"
      },
      "method": "Typical value printed in a materials data sheet, shown as less than 0.1",
      "status": "ground",
      "source": "wk-halar",
      "where": "Physical table, Water Absorption row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity",
      "value": 0.000375,
      "bound": "exact",
      "unit": "cal/cm-sec-°C",
      "scope": "material",
      "conditions": {
        "test_standard": "ASTM C177",
        "printed": "3.75 x 10-4 cal/cm-sec-°C (also 1.09 BTU-in/ft2-hr-°F)"
      },
      "method": "Typical value printed in a materials data sheet; printed value is 3.75 multiplied by 10-4, copied as 3.75e-4",
      "status": "ground",
      "source": "wk-halar",
      "where": "Thermal table, Thermal Conductivity row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "cte",
      "label": "Coefficient of linear thermal expansion",
      "value": 0.000056,
      "bound": "exact",
      "unit": "in/in/°F",
      "scope": "material",
      "conditions": {
        "test_standard": "ASTM D696",
        "printed": "5.6 x 10-5 in/in/°F"
      },
      "method": "Typical value printed in a materials data sheet; printed value is 5.6 multiplied by 10-5, copied as 5.6e-5",
      "status": "ground",
      "source": "wk-halar",
      "where": "Thermal table, Coefficient of Linear Thermal Expansion row",
      "source_detail": {
        "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
        "id": "Published 27 Feb 2025, typical values",
        "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
        "year": 2025,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "hardness",
      "label": "Hardness, Shore D",
      "value": 75,
      "bound": "exact",
      "unit": "Shore D",
      "scope": "material",
      "conditions": {
        "test_standard": "ASTM D2240",
        "form": "Halar 901 rod"
      },
      "method": "Printed value on a supplier product sheet",
      "status": "ground",
      "source": "pexco-ectfe",
      "where": "Hardness row",
      "source_detail": {
        "title": "Pexco ECTFE Rod product sheet (Halar 901 resin)",
        "id": "Pexco product sheet, February 2026",
        "url": "https://www.pexco.com/wp-content/uploads/2026/02/Pexco-ECTFE-Rod_productsheet_Feb2026.pdf",
        "year": 2026,
        "kind": "datasheet",
        "license": "supplier document, linked not reproduced"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Young's modulus (approximate)",
      "value": 1700,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "basis": "value printed in a reference encyclopedia article"
      },
      "method": "Value printed in a reference encyclopedia article",
      "status": "ground",
      "source": "wiki-ectfe",
      "where": "Physical and chemical properties section, sentence on impact strength and Young's modulus",
      "source_detail": {
        "title": "ECTFE (Wikipedia)",
        "id": "Wikipedia article, read in this run",
        "url": "https://en.wikipedia.org/wiki/ECTFE",
        "year": 2026,
        "kind": "web",
        "license": "CC BY-SA 4.0"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Atomic oxygen in low Earth orbit",
      "headline": "Atomic oxygen eroded ECTFE about as fast as Kapton H on the ISS, and far faster than PTFE (1.42e-25 cm3/atom).",
      "effect": "On the MISSE 2 flight ECTFE had an erosion yield of 1.79e-24 cm3/atom, against 3.00e-24 for Kapton H and 1.42e-25 for PTFE in the same table. FEP measured 2.00e-25 and PFA 1.73e-25.",
      "rating": "moderate",
      "conditions": {
        "flight": "MISSE 2, 3.95 years, fluence 8.43e21 atoms/cm2"
      },
      "source": "banks2008",
      "where": "Table I"
    },
    {
      "environment": "Acids, alkalis and organic solvents",
      "headline": "ECTFE resists most acids, alkalis and solvents, but not hot amines or ketones.",
      "effect": "The Halar data sheet says the material is resistant to most chemicals, including acids, alkalines and organic solvents, except hot amines and ketones. Wikipedia says its chemical resistance is similar to PTFE, though somewhat lower in some cases.",
      "rating": "unknown",
      "conditions": {
        "basis": "manufacturer and distributor data sheet, encyclopedia article"
      },
      "source": "wk-halar",
      "where": "General properties paragraph"
    },
    {
      "environment": "Ultraviolet light",
      "headline": "ECTFE has good UV resistance, particularly to UV-A and UV-B.",
      "effect": "No UV exposure number was read. The encyclopedia article states the material has good UV resistance, and films can be transparent.",
      "rating": "unknown",
      "conditions": {
        "basis": "qualitative statement only"
      },
      "source": "wiki-ectfe",
      "where": "Physical and chemical properties section"
    },
    {
      "environment": "Overheating above about 350 °C (decomposition)",
      "headline": "Above about 350 °C ECTFE breaks down and gives off hydrogen fluoride and other toxic gases.",
      "effect": "The Simona safety data sheet gives thermal decomposition from 350 °C and says that above this temperature the material breaks down into toxic fluorine-containing substances, and that burning gives hydrofluoric acid. The Halar 901S sheet lists hydrogen fluoride and hydrogen chloride as combustion products.",
      "rating": "severe",
      "conditions": {
        "trigger": "overheating or burning",
        "worst_case": "poor ventilation"
      },
      "source": "simona-sds",
      "where": "Section 10, Thermal decomposition and hazardous decomposition products"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "Halar 901S safety data sheet: the product is not labelled as hazardous under the regulation applied, but thermal decomposition can lead to release of toxic and corrosive gases. The thermal decomposition vapours of fluorinated polymers may cause polymer fume fever with flu-like symptoms.",
        "ghs": [],
        "source": "gfps-sds",
        "where": "Sections 2.2 and 2.3; Section 11, Effects"
      },
      {
        "text": "Halar 901S sheet threshold limits for hydrogen fluoride from thermal decomposition: ACGIH ceiling 2 ppm (USA); the sheet also lists TWA 0.5 ppm (ACGIH).",
        "ghs": [],
        "source": "gfps-sds",
        "where": "Section 8, threshold limit values of by-products from thermal decomposition"
      },
      {
        "text": "PubChem record for the copolymer (CAS 25101-45-5) gives no GHS hazard classification, and the material is listed as active under the EPA TSCA inventory.",
        "ghs": [],
        "source": "pubchem-ectfe",
        "where": "Sections 8.1 and 8.2"
      }
    ],
    "failure_risks": [
      {
        "mode": "Permeation by small molecules in lining service",
        "trigger": "Exposure of a lining to water vapour, oxygen, chlorine, hydrogen sulfide, HCl or HF",
        "consequence": "Small molecules permeate the matrix and can reach the underlying steel or fibre-reinforced plastic, which limits the lining lifetime.",
        "severity": "moderate",
        "source": "wiki-ectfe",
        "where": "Physical and chemical properties section"
      },
      {
        "mode": "Hydrogen fluoride release on overheating",
        "trigger": "Heating above about 350 °C",
        "consequence": "The polymer breaks down into toxic and corrosive gases, including hydrogen fluoride, which can cause severe lung injury.",
        "severity": "high",
        "source": "simona-sds",
        "where": "Section 10"
      }
    ],
    "side_effects": [
      {
        "text": "Thermal decomposition products can cause polymer fume fever in people, with flu-like symptoms.",
        "affects": "People handling hot material",
        "source": "gfps-sds",
        "where": "Section 11, Effects"
      }
    ],
    "handling": [
      {
        "text": "To avoid thermal decomposition, do not overheat the material and keep it away from heat and ignition sources. Take measures to prevent a build-up of static electricity.",
        "source": "gfps-sds",
        "where": "Section 7, handling advice"
      },
      {
        "text": "Keep the product away from tobacco and do not contaminate tobacco products with it.",
        "source": "gfps-sds",
        "where": "Section 7, handling advice"
      }
    ],
    "mitigations": [
      {
        "text": "Provide local ventilation suited to the decomposition risk. In case of decomposition use breathing apparatus with a face mask.",
        "source": "gfps-sds",
        "where": "Section 8 and Section 8.2 (exposure controls and firefighting)"
      }
    ]
  },
  "uses": [
    {
      "application": "electronics-and-chips",
      "device": "Primary and secondary jacketing of specialty data and heating cables, and wet benches for semiconductor processing",
      "example": "The encyclopedia article says ECTFE is used for cable jacketing where fire resistance and electrical properties matter, and that it has been widely used for wet tool and tubing systems for lithographic chemicals.",
      "source": "wiki-ectfe",
      "where": "Applications section"
    },
    {
      "application": "cryogenic-fuel",
      "device": "Gaskets for storing liquid oxygen and other propellants in aerospace systems",
      "example": "The encyclopedia article says ECTFE is used for manufacturing gaskets to store liquid oxygen and other propellants for aerospace applications, and that it keeps high impact strength in cryogenic applications.",
      "source": "wiki-ectfe",
      "where": "Applications and Physical and chemical properties sections"
    },
    {
      "application": "structures",
      "device": "Pipes, fittings, tanks and linings for the chemical industry",
      "example": "Halar sheet and pipe are used for chemical handling, process tanks, pump and valve components and wet-process tool parts, and the material is also used in sheet lining of metal and fibre-reinforced plastic.",
      "source": "wk-halar",
      "where": "General properties and Typical applications"
    }
  ],
  "supply": [
    {
      "subject": "Fluorine feedstock (fluorspar, calcium fluoride)",
      "producers": [
        {
          "country": "China",
          "share_percent": 60,
          "year": 2025
        },
        {
          "country": "Mexico",
          "share_percent": 15,
          "year": 2025
        },
        {
          "country": "Mongolia",
          "share_percent": 15,
          "year": 2025
        },
        {
          "country": "South Africa",
          "share_percent": 4.1,
          "year": 2025
        }
      ],
      "critical_lists": [],
      "recycling": "USGS: synthetic fluorspar may be produced from neutralization of waste in uranium enrichment, petroleum alkylation and stainless-steel pickling, though impurities constrain its use. Primary aluminum producers recycle HF and fluorides from smelting.",
      "substitutes": [
        "USGS: fluosilicic acid has been used as an alternative to fluorspar in making AlF3 and HF."
      ],
      "source": "usgs-mcs2026-fluorspar",
      "where": "World Mine Production table, 2025e. Shares are calculated by Space Mushroom as 2025e tonnes divided by the printed world total of 10,000 thousand t (China 6,000; Mexico 1,500; Mongolia 1,500; South Africa 410). Import sources 2021-24: Mexico 64 percent, Vietnam 12 percent, China 10 percent, South Africa 9 percent. Fluorspar is the feedstock for hydrogen fluoride, which is used to make the fluorine in fluoropolymers."
    },
    {
      "subject": "ECTFE resin producer",
      "producers": [],
      "critical_lists": [],
      "substitutes": [],
      "source": "wk-halar",
      "where": "The Halar trademark is registered to Solvay (Solvay Solexis); the Pexco sheet calls its resin 100 percent virgin Solvay Halar 901 ECTFE. No country shares for ECTFE resin makers were found, so none are entered."
    }
  ],
  "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": "Halar Materials Data Sheet (White Knight Fluid Handling, published 27 Feb 2025)",
      "type": "datasheet",
      "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
      "year": 2025
    },
    {
      "title": "Pexco ECTFE Rod product sheet (February 2026)",
      "type": "datasheet",
      "url": "https://www.pexco.com/wp-content/uploads/2026/02/Pexco-ECTFE-Rod_productsheet_Feb2026.pdf",
      "year": 2026
    },
    {
      "title": "Halar 901S Safety Data Sheet (GFPS, revision 08.09.2016)",
      "type": "sds",
      "url": "https://www.gfps.com/content/dam/gfps/us/products/piping-systems/sygef-ectfe/Extrusion%20-%20Halar%20901S-SDS_GB-EN-2.04.pdf",
      "year": 2016
    },
    {
      "title": "ECTFE Safety Data Sheet (Simona, distributed by Boedeker)",
      "type": "sds",
      "url": "https://www.boedeker.com/Portals/0/Safety%20Data%20Sheets%20SDS/Simona/ECTFE-SDS-Safety-Data-Sheet-Simona-Boedeker-2017.pdf",
      "year": 2017
    },
    {
      "title": "Mineral Commodity Summaries 2026: Fluorspar (USGS)",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-fluorspar.pdf",
      "year": 2026
    },
    {
      "title": "PubChem record for ethylene-chlorotrifluoroethylene copolymer (CID not assigned, CAS 25101-45-5)",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/25101-45-5",
      "year": 2026
    },
    {
      "title": "NIST Atomic Weights and Isotopic Compositions for All Elements",
      "type": "database",
      "url": "https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=C&all=all&ascii=html",
      "year": 2026
    }
  ],
  "gaps": [
    "No Solvay primary datasheet was opened. The values come from distributor and fabricator sheets that reproduce Solvay figures, and the file says so in each source.",
    "No radiation dose data for ECTFE was found or read. The tags do not list total-radiation-dose.",
    "No outgassing value for ECTFE was read from the NASA outgassing database or NASA RP-1124.",
    "No ECTFE radiation, cryogenic tensile or vacuum-UV number from a primary paper was read; the cryogenic statement is qualitative only.",
    "The polymerization process for ECTFE was not read in a fetched source, so the recipe gives composition only.",
    "No GHS classification was found; PubChem has none and the Halar 901S sheet is not labelled hazardous.",
    "No country shares for ECTFE resin producers were found.",
    "The Wikipedia article gives the Young's modulus as approximate (about 1700 MPa) without a test standard, so the entry is marked as approximate.",
    "Atomic weights for carbon and chlorine are printed by NIST as intervals, not single values; the file uses the printed interval lower bounds.",
    "No quantitative chemical-resistance table (for example a percent change in mass or strength) was opened.",
    "Hardness (Rockwell R93 on the Halar sheet) and flexural and compressive values were not entered as separate properties."
  ],
  "story": {
    "why": "ECTFE (Halar) is an alternating copolymer of ethylene and chlorotrifluoroethylene. Mixing hydrogen-bearing ethylene units with fluorinated units gives a material that is tougher than PTFE, while keeping the chemical resistance of a fluoropolymer. A data sheet gives a density of 1.68 g/cm3, a melting point of 238 °C and a heat deflection temperature of 115 °C at 264 psi. Wikipedia gives a continuous range of -76 °C to +150 °C and a tensile strength of about 7000 psi from the data sheet. ECTFE is used where a tough, chemically resistant and fire-resistant plastic is needed, such as linings, pipes and cable jackets.",
    "uses": [
      {
        "where": "Chemical lining and piping",
        "line": "Halar sheet and pipe are used in chemical handling, process tanks, pump and valve parts and wet-process tools; sheet lining is also applied to metal and fibre-reinforced plastic."
      },
      {
        "where": "Cable jacketing and semiconductor wet benches",
        "line": "ECTFE is used for primary and secondary jacketing of specialty cables and for wet tool and tubing systems for lithographic chemicals."
      },
      {
        "where": "Propellant gaskets",
        "line": "ECTFE is used to make gaskets for storing liquid oxygen and other propellants in aerospace systems."
      }
    ],
    "can_do": [
      {
        "label": "Atomic oxygen",
        "line": "On the MISSE 2 flight ECTFE eroded at 1.79e-24 cm3/atom over 3.95 years, against 3.00e-24 for Kapton H in the same table.",
        "scope": "material",
        "value": "1.79e-24 cm3/atom"
      },
      {
        "label": "Chemicals",
        "line": "The Halar data sheet says the material resists most chemicals, including acids, alkalines and organic solvents, except hot amines and ketones.",
        "scope": "material",
        "value": "Resistant to most acids and solvents"
      },
      {
        "label": "Heat",
        "line": "A data sheet gives a melting point of 238 °C (460 °F) and a maximum operating temperature of 149 °C, and Wikipedia gives a continuous range up to +150 °C.",
        "scope": "material",
        "value": "Melts at 238 °C"
      },
      {
        "label": "Electrical insulation",
        "line": "A data sheet gives a volume resistivity of 1e15 ohm-cm at 50 percent RH, a dielectric constant of 2.5 at 1 MHz and a dielectric strength of 500 V/mil.",
        "scope": "material",
        "value": "1e15 ohm-cm"
      }
    ],
    "compare": "In low Earth orbit ECTFE eroded at 1.79e-24 cm3/atom on the MISSE 2 flight, about the same as Kapton H at 3.00e-24 and far faster than PTFE (1.42e-25 cm3/atom) at 1.42e-25. For strength, a data sheet gives a tensile strength of 7000 psi for ECTFE and 8000 psi for a supplier's Halar 901 rod, and an elongation at break of 200 percent.",
    "compare_rows": [
      {
        "label": "Density",
        "benchmark": "density",
        "scope": "material"
      },
      {
        "label": "Max service temp",
        "benchmark": "max_service_temp",
        "scope": "material"
      },
      {
        "label": "Melting point",
        "benchmark": "melting_point",
        "scope": "material"
      }
    ],
    "handling": [
      "Keep the material away from heat and ignition sources, and never overheat it.",
      "Provide local ventilation suited to the decomposition risk, and avoid fume inhalation.",
      "Use breathing apparatus with a face mask if decomposition occurs.",
      "Take measures against static build-up when handling it."
    ],
    "good_for": [
      "Chemical linings and pipes. The data sheet says it resists most acids, alkalines and solvents.",
      "Tough, impact-resistant parts. The data sheet gives an elongation at break of 200 percent and a tensile strength of 7000 psi.",
      "Tough cable jackets with a continuous range of -76 °C to +150 °C.",
      "Low water absorption, below 0.1 percent over 24 hours."
    ],
    "watch_out": [
      "Atomic oxygen. On the MISSE 2 flight ECTFE eroded far faster than PTFE (1.42e-25 cm3/atom).",
      "Overheating. Above about 350 °C ECTFE releases hydrogen fluoride and other toxic gases.",
      "Permeation. Small molecules such as water and HF permeate the matrix and can limit a lining's lifetime.",
      "Hot amines and ketones attack it, according to the data sheet."
    ],
    "verdict": "ECTFE is a tough, chemically resistant fluoropolymer that is a good choice for linings, pipes and cable jackets on the ground. In low Earth orbit it erodes at about the same rate as Kapton H, so it is a poor choice for an exposed surface there. The flight erosion yield is the only space result here; the strength, density and electrical values are data-sheet typical values.",
    "recipe": {
      "line": "ECTFE is made by polymerizing ethylene and chlorotrifluoroethylene (CTFE) into an alternating copolymer, a semi-crystalline fluoropolymer (Wikipedia). The repeat unit is C4H4ClF3 with a molar mass of 144.5223 (NASA MISSE 2 table). The polymerization process was not read in a fetched source.",
      "parts": [
        {
          "name": "Carbon",
          "symbol": "C",
          "role": "Backbone carbons: two from ethylene and two from CTFE in each repeat unit."
        },
        {
          "name": "Hydrogen",
          "symbol": "H",
          "role": "Four hydrogens on the ethylene carbons, which give the copolymer its toughness compared with PTFE."
        },
        {
          "name": "Chlorine",
          "symbol": "Cl",
          "role": "One chlorine on the CTFE unit, which fills free volume and keeps permeation low."
        },
        {
          "name": "Fluorine",
          "symbol": "F",
          "role": "Three fluorines on the CTFE unit, which give chemical resistance.",
          "atoms": 3,
          "atomic_weight": 18.998403163
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "The solid is not labelled hazardous, but overheating ECTFE releases hydrogen fluoride and other toxic gases.",
        "points": [
          {
            "label": "The solid",
            "line": "The Halar 901S safety data sheet says the product is not labelled as hazardous, but thermal decomposition can release toxic and corrosive gases."
          },
          {
            "label": "Fume fever",
            "line": "Thermal decomposition vapours of fluorinated polymers may cause polymer fume fever, a flu-like illness."
          },
          {
            "label": "Above 350 °C",
            "line": "The Simona safety data sheet gives thermal decomposition from 350 °C, with hydrofluoric acid as a product of burning."
          }
        ],
        "level": 2,
        "verdict": "Not labelled hazardous as a solid; toxic fumes when…"
      },
      {
        "title": "If it fails",
        "lead": "These results come from a flight measurement, data sheets and a safety sheet, not from a reported failure of a flown ECTFE part.",
        "points": [
          {
            "label": "In orbit",
            "line": "On the MISSE 2 flight ECTFE eroded at 1.79e-24 cm3/atom, about the same as Kapton H (3.00e-24) and far faster than PTFE (1.42e-25 cm3/atom) (1.42e-25)."
          },
          {
            "label": "Overheating",
            "line": "Above about 350 °C the material breaks down into toxic fluorine-containing gases; the Halar sheet lists hydrogen fluoride as a combustion product."
          },
          {
            "label": "Lining permeation",
            "line": "Small molecules such as water, oxygen, chlorine and HF permeate the matrix and can limit the lifetime of a lining."
          }
        ]
      },
      {
        "title": "Handling and storage",
        "points": [
          {
            "label": "Do not overheat",
            "line": "Keep ECTFE away from heat and ignition sources, and do not overheat it."
          },
          {
            "label": "Ventilate",
            "line": "Provide local ventilation suited to the decomposition risk; in a fire use breathing apparatus with a face mask."
          },
          {
            "label": "Static",
            "line": "Take measures to prevent a build-up of static electricity when handling it."
          }
        ]
      }
    ]
  },
  "updated": "2026-10-20",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 21,
    "unreachable": 1,
    "caveats": 6,
    "note": "Written by an AI assistant on 2026-10-20 from pages fetched in this run. The NASA memorandum table, the White Knight and Pexco sheets, the Halar 901S and Simona safety data sheets, the USGS fluorspar summary, the PubChem record, the NIST atomic weights and the Wikipedia article were read directly. The Solvay primary datasheet was not reachable through search. No values were taken from memory or search snippets."
  },
  "sources": {
    "banks2008": {
      "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit",
      "id": "NASA/TM-2008-215490, NTRS 20090011780 (Banks, de Groh, Backus; December 2008)",
      "url": "https://ntrs.nasa.gov/citations/20090011780",
      "year": 2008,
      "kind": "report",
      "license": "public domain (NASA)"
    },
    "wk-halar": {
      "title": "Polyethylene Chlorotrifluoroethylene (ECTFE or Halar) Materials Data Sheet, White Knight Fluid Handling (a Graco company)",
      "id": "Published 27 Feb 2025, typical values",
      "url": "https://wkfluidhandling.com/wp-content/media/materials/ectfe-halar.pdf",
      "year": 2025,
      "kind": "datasheet",
      "license": "supplier document, linked not reproduced"
    },
    "pexco-ectfe": {
      "title": "Pexco ECTFE Rod product sheet (Halar 901 resin)",
      "id": "Pexco product sheet, February 2026",
      "url": "https://www.pexco.com/wp-content/uploads/2026/02/Pexco-ECTFE-Rod_productsheet_Feb2026.pdf",
      "year": 2026,
      "kind": "datasheet",
      "license": "supplier document, linked not reproduced"
    },
    "gfps-sds": {
      "title": "Halar 901S Safety Data Sheet (GFPS)",
      "id": "Revision 08.09.2016, version 2.04",
      "url": "https://www.gfps.com/content/dam/gfps/us/products/piping-systems/sygef-ectfe/Extrusion%20-%20Halar%20901S-SDS_GB-EN-2.04.pdf",
      "year": 2016,
      "kind": "datasheet",
      "license": "manufacturer document, linked not reproduced"
    },
    "simona-sds": {
      "title": "ECTFE Safety Data Sheet (Simona, distributed by Boedeker)",
      "id": "Simona ECTFE safety data sheet, 2017",
      "url": "https://www.boedeker.com/Portals/0/Safety%20Data%20Sheets%20SDS/Simona/ECTFE-SDS-Safety-Data-Sheet-Simona-Boedeker-2017.pdf",
      "year": 2017,
      "kind": "datasheet",
      "license": "manufacturer document, linked not reproduced"
    },
    "usgs-mcs2026-fluorspar": {
      "title": "Mineral Commodity Summaries 2026, Fluorspar (U.S. Geological Survey)",
      "id": "USGS MCS 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-fluorspar.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "pubchem-ectfe": {
      "title": "Ethylene-chlorotrifluoroethylene copolymer (PubChem Compound, CAS 25101-45-5)",
      "id": "PubChem record 25101-45-5, read in this run",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/25101-45-5",
      "year": 2026,
      "kind": "database",
      "license": "PubChem (NLM) terms"
    },
    "nist-atomic-weights": {
      "title": "Atomic Weights and Isotopic Compositions for All Elements (NIST)",
      "id": "NIST composition tables, read in this run",
      "url": "https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=C&all=all&ascii=html",
      "year": 2026,
      "kind": "database",
      "license": "public domain (NIST)"
    },
    "wiki-ectfe": {
      "title": "ECTFE (Wikipedia)",
      "id": "Wikipedia article, read in this run",
      "url": "https://en.wikipedia.org/wiki/ECTFE",
      "year": 2026,
      "kind": "web",
      "license": "CC BY-SA 4.0"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/ectfe-halar/"
}