{
  "spore": "profile",
  "id": "phenolic-resin",
  "spore_version": "0.2",
  "family": "engineering-polymers",
  "name": "Phenolic resin (phenol-formaldehyde; Bakelite and phenolic laminates)",
  "abbreviation": "PF",
  "role": "thermosetting resin for ablative heat shields, laminates and moulded parts",
  "category": "polymers",
  "type": "epoxies-and-resins",
  "summary": "Phenolic resin is a thermoset made by condensing phenol with formaldehyde. Cured, it forms a hard, insoluble network. Bakelite was the first commercial form, developed in 1907 and patented in 1909. NASA's PICA heat shield is a carbon fibre felt impregnated with phenolic resin; it was the Stardust heatshield and is the forebody heatshield for Mars Science Laboratory and the SpaceX Dragon. In a 2019 NASA comparison, the heritage phenolic resin SC1008 left 49% char in inert gas but decomposed from 375 degC, with a lower char yield and a lower glass transition than the newer resins tested.\n",
  "best_for": "Char-forming ablators and laminates for gears and bearings, where a hard, machinable thermoset is needed (NEMA LE cotton phenolic: 13 ksi lengthwise tensile)",
  "weakest_at": "Low char yield and low decomposition onset compared with polyimide and cyanate ester, and a lower glass transition than cyanate ester and polybenzoxazine (NASA)",
  "identity": {
    "formula": "Phenol polymer with formaldehyde (CAS 9003-35-4): a cross-linked network made by condensing phenol with formaldehyde",
    "cas": "9003-35-4",
    "designations": [
      {
        "system": "Trade name",
        "code": "Bakelite",
        "source": "wiki-bakelite",
        "where": "Article title and first paragraph"
      }
    ],
    "source": "mersen-sds",
    "where": "Composition table (ingredients), first row: Phenol polymer with formaldehyde, CAS-No. 9003-35-4"
  },
  "tags": {
    "environments": [
      "re-entry"
    ],
    "stresses": [
      "high-heat-flux",
      "humidity"
    ],
    "applications": [
      "heat-shields",
      "mechanisms",
      "electronics-and-chips"
    ]
  },
  "properties": [
    {
      "benchmark": "density",
      "label": "Density, cured phenolic resin SC1008 (heritage ablative resin)",
      "value": 1.21,
      "bound": "exact",
      "unit": "g/cc",
      "scope": "material",
      "conditions": {
        "resin": "SC1008 heritage phenolic, cured neat resin without a reinforcing matrix",
        "basis": "compression-test specimens of cured resin"
      },
      "method": "Density column of the resin table in the NASA resin characterization (ERC Inc. and NASA Ames), as printed",
      "status": "ground",
      "source": "boghozian2019",
      "where": "Resin density table, Phenolic resin row (slide on compression-test samples)",
      "source_detail": {
        "title": "Characterization of New TPS Resins",
        "id": "NTRS 20190033961; T. Boghozian (ERC International), M. Stackpoole (NASA Ames), G. Gonzales (ERC International); NSMMS and CRASTE Joint Symposia, June 2019",
        "url": "https://ntrs.nasa.gov/citations/20190033961",
        "year": 2019,
        "kind": "report",
        "license": "NASA NTRS public record"
      }
    },
    {
      "benchmark": "decomposition_temperature",
      "label": "Decomposition temperature, cured phenolic resin SC1008",
      "value": 375,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "resin": "SC1008 heritage phenolic, cured neat resin",
        "atmosphere": "inert gas",
        "heating_rate": "10 C/min"
      },
      "method": "Thermogravimetric analysis, decomposition temperature column, as printed",
      "status": "ground",
      "source": "boghozian2019",
      "where": "TGA results table, SC1008 row (Decomposition temperature column)",
      "source_detail": {
        "title": "Characterization of New TPS Resins",
        "id": "NTRS 20190033961; T. Boghozian (ERC International), M. Stackpoole (NASA Ames), G. Gonzales (ERC International); NSMMS and CRASTE Joint Symposia, June 2019",
        "url": "https://ntrs.nasa.gov/citations/20190033961",
        "year": 2019,
        "kind": "report",
        "license": "NASA NTRS public record"
      }
    },
    {
      "benchmark": "char_yield",
      "label": "Char yield, cured phenolic resin SC1008",
      "value": 49,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "resin": "SC1008 heritage phenolic, cured neat resin",
        "atmosphere": "inert gas",
        "heating_rate": "10 C/min"
      },
      "method": "Thermogravimetric analysis, char yield column, as printed; non-canonical benchmark name",
      "status": "ground",
      "source": "boghozian2019",
      "where": "TGA results table, SC1008 row (Char Yield column)",
      "source_detail": {
        "title": "Characterization of New TPS Resins",
        "id": "NTRS 20190033961; T. Boghozian (ERC International), M. Stackpoole (NASA Ames), G. Gonzales (ERC International); NSMMS and CRASTE Joint Symposia, June 2019",
        "url": "https://ntrs.nasa.gov/citations/20190033961",
        "year": 2019,
        "kind": "report",
        "license": "NASA NTRS public record"
      }
    },
    {
      "benchmark": "density",
      "label": "Density, LE-675 cotton fabric phenolic laminate",
      "value": 1.32,
      "bound": "exact",
      "unit": "g/cc",
      "scope": "material",
      "conditions": {
        "grade": "LE-675 (Phenolite, cotton fabric based laminate)"
      },
      "method": "Density row of the Phenolite grade table, as printed (GM/CC)",
      "status": "ground",
      "source": "midwest-phenolite",
      "where": "Grade table, row Density, LE-675 column",
      "source_detail": {
        "title": "Phenolite cotton fabric based laminate grade specifications",
        "id": "Midwest Composites, cotspecs grade table (undated page)",
        "url": "https://midwestcomposites.clearlight.com/cotspecs.htm",
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited"
      }
    },
    {
      "benchmark": "density",
      "label": "Specific gravity, NEMA LE cotton phenolic laminate",
      "value": 1.34,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "grade": "NEMA LE (natural or black), cotton based phenolic laminate"
      },
      "method": "Specific gravity printed in the typical values table; test method not printed for this row",
      "status": "ground",
      "source": "gund-datasheet",
      "where": "Typical values table, Specific Gravity row, NEMA LE column",
      "source_detail": {
        "title": "NEMA C, CE, LE Phenolic Resin Cotton Cloth technical data sheet",
        "id": "The Gund Company, TCGR 03/2023",
        "url": "https://thegundcompany.com/wp-content/uploads/2025/12/NEMA-C-CE-LE-Phenolic-Resin-Cotton-Cloth-by-The-Gund-Co.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited"
      }
    },
    {
      "benchmark": "flash_point",
      "label": "Flash point, uncured phenolic resin product ACE PGY",
      "value": 100,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "product": "ACE PGY uncured phenolic resin (liquid)",
        "basis": "printed as at least 100 degC (lower limit)"
      },
      "method": "Physical properties section of the safety data sheet, as printed with a greater-than-or-equal sign",
      "status": "ground",
      "source": "mersen-sds",
      "where": "Physical and chemical properties section, Flash point row",
      "source_detail": {
        "title": "ACE PGY phenolic resin, safety data sheet (English)",
        "id": "Mersen, 2023",
        "url": "https://de.mersen.com/sites/default/files/files_imported/ace-pgy-phenolic-resin-english-2023.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "manufacturer SDS, cited"
      }
    },
    {
      "benchmark": "max_service_temp",
      "label": "Maximum operating temperature, NEMA LE laminate",
      "value": 125,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "grade": "NEMA LE",
        "basis": "maximum operating temperature, typical value, no time limit printed"
      },
      "method": "Typical values table, Maximum Operating Temperature row; the degree sign is missing in the PDF text layer and reads as 0C there",
      "status": "ground",
      "source": "gund-datasheet",
      "where": "Typical values table, Maximum Operating Temperature row, NEMA LE column",
      "source_detail": {
        "title": "NEMA C, CE, LE Phenolic Resin Cotton Cloth technical data sheet",
        "id": "The Gund Company, TCGR 03/2023",
        "url": "https://thegundcompany.com/wp-content/uploads/2025/12/NEMA-C-CE-LE-Phenolic-Resin-Cotton-Cloth-by-The-Gund-Co.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited"
      }
    },
    {
      "benchmark": "max_service_temp",
      "label": "Continuous heat resistance, LE-675 laminate (printed in Fahrenheit)",
      "value": 250,
      "bound": "exact",
      "unit": "°F",
      "scope": "material",
      "conditions": {
        "grade": "LE-675",
        "basis": "heat resistance, continuous, as printed in Fahrenheit"
      },
      "method": "Grade table row Heat Resistance, Farenheit, Continuous, as printed",
      "status": "ground",
      "source": "midwest-phenolite",
      "where": "Grade table, Heat Resistance row, LE-675 column",
      "source_detail": {
        "title": "Phenolite cotton fabric based laminate grade specifications",
        "id": "Midwest Composites, cotspecs grade table (undated page)",
        "url": "https://midwestcomposites.clearlight.com/cotspecs.htm",
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength lengthwise, NEMA LE laminate",
      "value": 90,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "grade": "NEMA LE, 0.125 in thickness",
        "direction": "lengthwise"
      },
      "method": "Tensile strength row, ASTM D-638, printed as 13 (90) ksi (MPa); the MPa figure is recorded",
      "status": "ground",
      "source": "gund-datasheet",
      "where": "Key characteristics table, Tensile Strength Lengthwise row, NEMA LE column",
      "source_detail": {
        "title": "NEMA C, CE, LE Phenolic Resin Cotton Cloth technical data sheet",
        "id": "The Gund Company, TCGR 03/2023",
        "url": "https://thegundcompany.com/wp-content/uploads/2025/12/NEMA-C-CE-LE-Phenolic-Resin-Cotton-Cloth-by-The-Gund-Co.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength crosswise, NEMA LE laminate",
      "value": 62,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "grade": "NEMA LE, 0.125 in thickness",
        "direction": "crosswise"
      },
      "method": "Tensile strength row, ASTM D-638, printed as 9 (62) ksi (MPa); the MPa figure is recorded",
      "status": "ground",
      "source": "gund-datasheet",
      "where": "Key characteristics table, Tensile Strength Crosswise row, NEMA LE column",
      "source_detail": {
        "title": "NEMA C, CE, LE Phenolic Resin Cotton Cloth technical data sheet",
        "id": "The Gund Company, TCGR 03/2023",
        "url": "https://thegundcompany.com/wp-content/uploads/2025/12/NEMA-C-CE-LE-Phenolic-Resin-Cotton-Cloth-by-The-Gund-Co.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength lengthwise, LE-675 laminate",
      "value": 13500,
      "bound": "exact",
      "unit": "psi",
      "scope": "material",
      "conditions": {
        "grade": "LE-675",
        "direction": "lengthwise"
      },
      "method": "Grade table row Tensile Strength, PSI, Lengthwise, as printed (13,500 PSI)",
      "status": "ground",
      "source": "midwest-phenolite",
      "where": "Grade table, Tensile Strength Lengthwise row, LE-675 column",
      "source_detail": {
        "title": "Phenolite cotton fabric based laminate grade specifications",
        "id": "Midwest Composites, cotspecs grade table (undated page)",
        "url": "https://midwestcomposites.clearlight.com/cotspecs.htm",
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited"
      }
    },
    {
      "benchmark": "flexural_strength",
      "label": "Flexural strength lengthwise, NEMA LE laminate",
      "value": 152,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "grade": "NEMA LE",
        "direction": "lengthwise"
      },
      "method": "Flexural strength row, printed as 22 (152) ksi (MPa); the test method is printed as ASTM D-695 on that row",
      "status": "ground",
      "source": "gund-datasheet",
      "where": "Key characteristics table, Flexural Strength Lengthwise row, NEMA LE column",
      "source_detail": {
        "title": "NEMA C, CE, LE Phenolic Resin Cotton Cloth technical data sheet",
        "id": "The Gund Company, TCGR 03/2023",
        "url": "https://thegundcompany.com/wp-content/uploads/2025/12/NEMA-C-CE-LE-Phenolic-Resin-Cotton-Cloth-by-The-Gund-Co.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited"
      }
    },
    {
      "benchmark": "flexural_strength",
      "label": "Flexural strength crosswise, NEMA LE laminate",
      "value": 110,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "grade": "NEMA LE",
        "direction": "crosswise"
      },
      "method": "Flexural strength row, printed as 16 (110) ksi (MPa); the test method is printed as ASTM D-695 on that row",
      "status": "ground",
      "source": "gund-datasheet",
      "where": "Key characteristics table, Flexural Strength Crosswise row, NEMA LE column",
      "source_detail": {
        "title": "NEMA C, CE, LE Phenolic Resin Cotton Cloth technical data sheet",
        "id": "The Gund Company, TCGR 03/2023",
        "url": "https://thegundcompany.com/wp-content/uploads/2025/12/NEMA-C-CE-LE-Phenolic-Resin-Cotton-Cloth-by-The-Gund-Co.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited"
      }
    },
    {
      "benchmark": "shear_strength",
      "label": "Shear strength, NEMA LE laminate",
      "value": 93,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "grade": "NEMA LE"
      },
      "method": "Shear strength row, ASTM D-732, printed as 13.5 (93) ksi (MPa); the MPa figure is recorded",
      "status": "ground",
      "source": "gund-datasheet",
      "where": "Key characteristics table, Shear Strength row, NEMA LE column",
      "source_detail": {
        "title": "NEMA C, CE, LE Phenolic Resin Cotton Cloth technical data sheet",
        "id": "The Gund Company, TCGR 03/2023",
        "url": "https://thegundcompany.com/wp-content/uploads/2025/12/NEMA-C-CE-LE-Phenolic-Resin-Cotton-Cloth-by-The-Gund-Co.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited"
      }
    },
    {
      "benchmark": "moisture_absorption",
      "label": "Moisture absorption, NEMA LE laminate",
      "value": 1.9,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "grade": "NEMA LE",
        "test": "ASTM D-570 (test exposure not printed on the sheet)"
      },
      "method": "Moisture absorption row, ASTM D-570, as printed",
      "status": "ground",
      "source": "gund-datasheet",
      "where": "Key characteristics table, Moisture Absorption row, NEMA LE column",
      "source_detail": {
        "title": "NEMA C, CE, LE Phenolic Resin Cotton Cloth technical data sheet",
        "id": "The Gund Company, TCGR 03/2023",
        "url": "https://thegundcompany.com/wp-content/uploads/2025/12/NEMA-C-CE-LE-Phenolic-Resin-Cotton-Cloth-by-The-Gund-Co.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited"
      }
    },
    {
      "benchmark": "dielectric_strength",
      "label": "Dielectric strength, NEMA LE laminate, Condition A",
      "value": 625,
      "bound": "exact",
      "unit": "V/mil",
      "scope": "material",
      "conditions": {
        "grade": "NEMA LE",
        "thickness": "0.062 in",
        "condition": "A (as printed)"
      },
      "method": "Dielectric strength row, Condition A column, as printed in V/mil",
      "status": "ground",
      "source": "gund-datasheet",
      "where": "Key characteristics table, Dielectric Strength (0.062 in) row, Condition A, NEMA LE column",
      "source_detail": {
        "title": "NEMA C, CE, LE Phenolic Resin Cotton Cloth technical data sheet",
        "id": "The Gund Company, TCGR 03/2023",
        "url": "https://thegundcompany.com/wp-content/uploads/2025/12/NEMA-C-CE-LE-Phenolic-Resin-Cotton-Cloth-by-The-Gund-Co.pdf",
        "year": 2023,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Thermal decomposition in inert gas, heated at 10 C/min (thermogravimetric analysis)",
      "headline": "The heritage cured phenolic starts to decompose at 375 °C and leaves 49% char.",
      "effect": "Decomposition begins at 375 °C and the char yield is 49%, lower than polyimide and cyanate ester in the same table. NASA lists low char yield and low decomposition onset as phenolic weaknesses.",
      "rating": "moderate",
      "conditions": {
        "atmosphere": "inert gas",
        "heating_rate": "10 C/min"
      },
      "source": "boghozian2019",
      "where": "TGA results table; Objective and Motivation slide"
    },
    {
      "environment": "Continuous service temperature (NEMA LE laminate, typical value)",
      "headline": "The datasheet prints a maximum operating temperature of 125 °C and no ageing data.",
      "effect": "The sheet gives a typical maximum operating temperature only. No time at temperature or property retention is printed, so the rating is unknown.",
      "rating": "unknown",
      "conditions": {
        "grade": "NEMA LE"
      },
      "source": "gund-datasheet",
      "where": "Typical values table, Maximum Operating Temperature row"
    },
    {
      "environment": "Humidity, ASTM D-570 moisture absorption (NEMA LE laminate)",
      "headline": "The laminate absorbs 1.9% moisture under the ASTM D-570 test.",
      "effect": "Moisture absorption is printed as 1.9%. The same sheet prints 3.5% for the NEMA C grade, so the LE grade absorbs less moisture than C.",
      "rating": "low",
      "conditions": {
        "grade": "NEMA LE",
        "test": "ASTM D-570"
      },
      "source": "gund-datasheet",
      "where": "Key characteristics table, Moisture Absorption row"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "Mersen safety data sheet for the uncured ACE PGY phenolic resin: signal word Danger; causes severe skin burns and eye damage (H314), may cause an allergic skin reaction (H317) and is harmful if inhaled (H332).",
        "ghs": [
          "H314",
          "H317",
          "H332"
        ],
        "source": "mersen-sds",
        "where": "Hazard statements (CLP) block of the safety data sheet"
      },
      {
        "text": "The same SDS also lists suspected genetic defects (H341), may cause cancer (H350), may damage fertility or the unborn child (H360), may cause organ damage on repeated exposure (H373) and harmful to aquatic life with long lasting effects (H412).",
        "ghs": [
          "H341",
          "H350",
          "H360",
          "H373",
          "H412"
        ],
        "source": "mersen-sds",
        "where": "Hazard statements (CLP) block of the safety data sheet"
      }
    ],
    "failure_risks": [
      {
        "mode": "Thermal decomposition of the cured resin",
        "trigger": "Heating above the onset in inert gas at 10 C/min",
        "consequence": "Mass loss starts at 375 °C; the heritage resin leaves 49% char.",
        "severity": "moderate",
        "source": "boghozian2019",
        "where": "TGA results table, SC1008 row"
      },
      {
        "mode": "Softening as the matrix nears its glass transition",
        "trigger": "Heating toward the glass transition temperature of the resin",
        "consequence": "NASA reports that phenolic has a lower glass transition than cyanate ester and polybenzoxazine, so the matrix softens sooner and mechanical properties drop. The Tg value itself was not read.",
        "severity": "moderate",
        "source": "boghozian2019",
        "where": "Glass transition slide, phenolic comparison"
      },
      {
        "mode": "Lot-to-lot density variation in carbon-phenolic ablator billets",
        "trigger": "Manufacturing spread in PICA billets",
        "consequence": "NASA notes significant density variation in PICA billets, which matters for lot acceptance and for thermal sizing.",
        "severity": "low",
        "source": "ellerby2019",
        "where": "Slide titled PICA Billet Has Significant Variability in Density"
      },
      {
        "mode": "Moisture uptake in service",
        "trigger": "Humid air or immersion (ASTM D-570 test)",
        "consequence": "The NEMA LE laminate absorbs 1.9% moisture by mass under the printed test.",
        "severity": "low",
        "source": "gund-datasheet",
        "where": "Key characteristics table, Moisture Absorption row"
      }
    ],
    "side_effects": [],
    "handling": [
      {
        "text": "Wear gloves and eye protection; the SDS classes the uncured resin as causing severe skin burns and eye damage and as a skin sensitiser.",
        "source": "mersen-sds",
        "where": "Hazard statements (CLP) block; handling section"
      },
      {
        "text": "During processing, vapours of phenol and benzaldehyde may be released; use ventilation, and an approved respirator when exposed to vapours from heated material, as the SDS advises.",
        "source": "mersen-sds",
        "where": "Additional hazards when processed; exposure controls section"
      }
    ],
    "mitigations": []
  },
  "uses": [
    {
      "application": "heat-shields",
      "device": "Ablative heatshield, PICA carbon phenolic",
      "example": "PICA, a carbon fibre insulation impregnated with phenolic resin, was the Stardust heatshield and is the forebody heatshield for Mars Science Laboratory and the SpaceX Dragon.",
      "source": "milos-pica2009",
      "where": "Section I (Introduction)"
    },
    {
      "application": "heat-shields",
      "device": "Phenolic-nylon charring ablator test material (1960s)",
      "example": "The high-density phenolic-nylon ablator in a 1965 NASA study was 50% by weight Union Carbide Bakelite BRP-5549 phenolic resin.",
      "source": "tnd2991-1965",
      "where": "Test materials, high-density phenolic-nylon description"
    },
    {
      "application": "mechanisms",
      "device": "Gears, pinions and bearings",
      "example": "The Gund datasheet describes NEMA C, CE and LE cotton phenolic laminates as suited to gears, pinions and bearings.",
      "source": "gund-datasheet",
      "where": "Product description paragraph"
    },
    {
      "application": "electronics-and-chips",
      "device": "Electrical insulating bushings",
      "example": "The earliest commercial electrical use of Bakelite was insulating bushings made in 1908 for the Weston Electrical Instrument Corporation.",
      "source": "wiki-bakelite",
      "where": "Main uses section"
    }
  ],
  "supply": [],
  "media": [],
  "documents": [
    {
      "title": "ACE PGY phenolic resin, safety data sheet (English)",
      "type": "sds",
      "url": "https://de.mersen.com/sites/default/files/files_imported/ace-pgy-phenolic-resin-english-2023.pdf"
    },
    {
      "title": "NEMA C, CE, LE Phenolic Resin Cotton Cloth technical data sheet",
      "type": "datasheet",
      "url": "https://thegundcompany.com/wp-content/uploads/2025/12/NEMA-C-CE-LE-Phenolic-Resin-Cotton-Cloth-by-The-Gund-Co.pdf"
    },
    {
      "title": "Characterization of New TPS Resins",
      "type": "report",
      "url": "https://ntrs.nasa.gov/citations/20190033961"
    },
    {
      "title": "Ablation and Thermal Response Property Model Validation for Phenolic Impregnated Carbon Ablator",
      "type": "paper",
      "url": "https://ntrs.nasa.gov/citations/20110012891"
    }
  ],
  "gaps": [
    "No glass transition temperature for the cured phenolic was read. The NASA resin slide gives a 260 degC value but does not tie it to a resin clearly, so no Tg is used.",
    "No UV, atomic oxygen or chemical resistance data for cured phenolic was read. The one ageing search returned no UV or hygrothermal study for cured phenolic.",
    "No thermal ageing data beyond the continuous service limit printed on the datasheet.",
    "No supply data: producer country shares for phenol and formaldehyde were not found in a source read in this run. The Wikipedia phenol article names the cumene process as dominant but gives no country shares.",
    "Critical-mineral status was not checked; the feedstocks are petrochemical and no USGS or EU list entry was opened.",
    "The PubChem GHS summary for CAS 9003-35-4 could not be read (reCAPTCHA page). Hazards come from the Mersen SDS for one uncured resin product only.",
    "Hazard data apply to the uncured ACE PGY resin, not to a cured laminate or the NEMA grades.",
    "PICA numeric properties (density, thermal conductivity, heat capacity, char density) are not printed in the Milos and Chen paper, which withholds them under export control, and the 2019 NASA slides show only normalised plots. No numeric PICA or carbon-phenolic property was read.",
    "A Japanese carbon-phenolic density range appeared only in a search snippet and is not used.",
    "Non-canonical benchmark names in use: decomposition_temperature and char_yield are not in spores/property-canon.yaml.",
    "Designations: NEMA LI-1 grade codes (C, CE, LE) and IEC 60893 codes (PFCC 201, 202, 204) do not fit the designation systems list, so they are not recorded.",
    "No thermoset type exists in src/data/taxonomy.ts. The closest type, epoxies-and-resins, is used.",
    "The Gund datasheet prints the maximum operating temperature unit with the degree sign lost in the PDF text layer; 125 is read in degrees Celsius from the same row.",
    "The Midwest Composites page gives LE-675 lengthwise tensile as 13,500 PSI; an earlier search snippet gave 14,000, which is not used."
  ],
  "story": {
    "why": "Phenolic resins are used where a char-forming, heat-resistant thermoset is needed. PICA, a carbon fibre felt impregnated with phenolic resin, has flown as a heat shield on Stardust and is used on Mars Science Laboratory and SpaceX Dragon. Phenolic laminates are used for gears, pinions and bearings because they are tough and machinable. NASA's comparison shows the heritage resin's weak points, low char yield and a low decomposition onset.",
    "uses": [
      {
        "where": "Heat shields",
        "line": "PICA, a phenolic-impregnated carbon ablator, was the Stardust heatshield and is the forebody heatshield for Mars Science Laboratory and SpaceX Dragon."
      },
      {
        "where": "Gears and bearings",
        "line": "NEMA LE cotton phenolic laminate is printed as suited to gears, pinions and bearings, with a 90 MPa lengthwise tensile strength."
      }
    ],
    "can_do": [
      {
        "label": "Char yield",
        "line": "The heritage resin SC1008 left 49% char at 10 C/min in inert gas.",
        "scope": "material",
        "value": "49%"
      },
      {
        "label": "Cured resin density",
        "line": "The cured SC1008 resin has a density of 1.21 g/cc, as printed in the NASA resin table.",
        "scope": "material",
        "value": "1.21 g/cc"
      },
      {
        "label": "Continuous service",
        "line": "The NEMA LE laminate has a printed maximum operating temperature of 125 °C.",
        "scope": "material",
        "value": "125 °C"
      }
    ],
    "compare": "Phenolic is the heritage ablative resin. NASA's 2019 resin study compared it with cyanate ester, polybenzoxazine, polyimidazole and polyimide. Phenolic had a lower char yield and a lower decomposition onset than polyimide and cyanate ester in the same table, and a lower glass transition than cyanate ester and polybenzoxazine. The laminate grades are cotton based; their tensile values are typical, not specification values.",
    "compare_rows": [
      {
        "label": "Density",
        "benchmark": "density",
        "scope": "material"
      },
      {
        "label": "Maximum service temperature",
        "benchmark": "max_service_temp",
        "scope": "material"
      },
      {
        "label": "Flexural strength",
        "benchmark": "flexural_strength",
        "scope": "material"
      }
    ],
    "handling": [
      "Wear gloves and eye protection; the uncured resin is corrosive to skin and eyes and is a skin sensitiser.",
      "Process with ventilation; phenol and benzaldehyde vapours are released during processing."
    ],
    "good_for": [
      "Char-forming heat shields, where the char carries heat away on re-entry.",
      "Machinable laminate gears, pinions and bearings made from cotton phenolic grades."
    ],
    "watch_out": [
      "Low char yield and a low decomposition onset compared with polyimide and cyanate ester.",
      "Lower glass transition than cyanate ester and polybenzoxazine, so the matrix softens earlier.",
      "PICA billets vary in density, which changes thermal sizing and lot acceptance."
    ],
    "verdict": "Phenolic resin is a proven, cheap heat-shield and laminate resin with heritage flight use, but NASA's own comparison shows low char yield and a low glass transition. Newer resins are being developed to beat it.",
    "recipe": {
      "line": "Phenol and formaldehyde react in a condensation reaction, with an acid or base catalyst, to give a soluble intermediate that hardens under heat and pressure into an insoluble, hard resin. Phenol is made mainly by the cumene process, the dominant industrial route.",
      "parts": [
        {
          "name": "Phenol",
          "role": "The aromatic monomer; its hydroxyl-bearing ring joins to formaldehyde at the ring positions to build the network."
        },
        {
          "name": "Formaldehyde",
          "role": "The cross-linking monomer that links phenol rings together."
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "The uncured ACE PGY resin is classed in the Mersen SDS as corrosive to skin and eyes and as a skin sensitiser.",
        "points": [
          {
            "label": "Skin and eyes",
            "line": "Causes severe skin burns and eye damage (H314) and may cause an allergic skin reaction (H317), per the SDS."
          }
        ],
        "level": 0,
        "verdict": "Uncured resin corrosive and a sensitiser"
      },
      {
        "title": "In heating",
        "lead": "Heritage phenolic gives 49% char in inert gas but starts to decompose at 375 degC, with a lower glass transition than the newer resins NASA tested.",
        "points": [
          {
            "label": "Char",
            "line": "The heritage resin SC1008 leaves 49% char at 10 C/min in inert gas."
          }
        ],
        "verdict": "Chars well, softens and decomposes early"
      }
    ]
  },
  "updated": "2026-10-26",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 16,
    "unreachable": 0,
    "caveats": 9,
    "note": "Written by an AI assistant from pages and PDFs read in this run; 16 values, 9 sources. Tg, UV and atomic oxygen ageing, supply shares and PICA numeric properties were not found in a readable source."
  },
  "sources": {
    "boghozian2019": {
      "title": "Characterization of New TPS Resins",
      "id": "NTRS 20190033961; T. Boghozian (ERC International), M. Stackpoole (NASA Ames), G. Gonzales (ERC International); NSMMS and CRASTE Joint Symposia, June 2019",
      "url": "https://ntrs.nasa.gov/citations/20190033961",
      "year": 2019,
      "kind": "report",
      "license": "NASA NTRS public record"
    },
    "gund-datasheet": {
      "title": "NEMA C, CE, LE Phenolic Resin Cotton Cloth technical data sheet",
      "id": "The Gund Company, TCGR 03/2023",
      "url": "https://thegundcompany.com/wp-content/uploads/2025/12/NEMA-C-CE-LE-Phenolic-Resin-Cotton-Cloth-by-The-Gund-Co.pdf",
      "year": 2023,
      "kind": "datasheet",
      "license": "manufacturer datasheet, cited"
    },
    "midwest-phenolite": {
      "title": "Phenolite cotton fabric based laminate grade specifications",
      "id": "Midwest Composites, cotspecs grade table (undated page)",
      "url": "https://midwestcomposites.clearlight.com/cotspecs.htm",
      "kind": "datasheet",
      "license": "manufacturer datasheet, cited"
    },
    "mersen-sds": {
      "title": "ACE PGY phenolic resin, safety data sheet (English)",
      "id": "Mersen, 2023",
      "url": "https://de.mersen.com/sites/default/files/files_imported/ace-pgy-phenolic-resin-english-2023.pdf",
      "year": 2023,
      "kind": "datasheet",
      "license": "manufacturer SDS, cited"
    },
    "wiki-bakelite": {
      "title": "Bakelite",
      "id": "Wikipedia article, read 2026-10-26",
      "url": "https://en.wikipedia.org/wiki/Bakelite",
      "kind": "web",
      "license": "CC BY-SA 4.0"
    },
    "wiki-phenol": {
      "title": "Phenol",
      "id": "Wikipedia article, read 2026-10-26",
      "url": "https://en.wikipedia.org/wiki/Phenol",
      "kind": "web",
      "license": "CC BY-SA 4.0"
    },
    "milos-pica2009": {
      "title": "Ablation and Thermal Response Property Model Validation for Phenolic Impregnated Carbon Ablator",
      "id": "AIAA-2009-0262; F.S. Milos and Y.-K. Chen, NASA Ames, 47th AIAA Aerospace Sciences Meeting, January 2009; NTRS 20110012891",
      "url": "https://ntrs.nasa.gov/citations/20110012891",
      "year": 2009,
      "kind": "paper",
      "license": "NASA NTRS public record"
    },
    "ellerby2019": {
      "title": "Thermal Properties - Do We Trust Them? Yes'ish (panel discussion slides)",
      "id": "Don Ellerby, NASA Ames; 30th Annual Thermal and Fluids Analysis Workshop, August 26, 2019; NTRS 20190030277",
      "url": "https://ntrs.nasa.gov/api/citations/20190030277/downloads/20190030277.pdf",
      "year": 2019,
      "kind": "report",
      "license": "NASA NTRS public record"
    },
    "tnd2991-1965": {
      "title": "Thermophysical properties of six charring ablators from 140 to 700 K and two chars from 800 to 3000 K",
      "id": "NASA TN D-2991, 1965; NTRS 19650024901",
      "url": "https://ntrs.nasa.gov/citations/19650024901",
      "year": 1965,
      "kind": "report",
      "license": "NASA NTRS public record"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/phenolic-resin/"
}