spore: profile
id: nomex
spore_version: 0.2
family: glass-and-composites
name: Nomex meta-aramid fibre and fabric
abbreviation: Nomex
role: meta-aramid fibre and paper for spacesuit layers, thermal blankets and honeycomb
category: textiles
type: nomex-fabric
summary: |
  Nomex is a meta-aramid, poly(m-phenylene isophthalamide), sold by DuPont as fibre, paper and pressboard. The DuPont characteristics page for the Nomex 400 series prints a continuous service temperature of 220 °C for at least 10 years, a limiting oxygen index above 20.8 at 220 °C, and 800 megarads (8 MGy) of ionizing radiation before the paper is essentially unaffected. On the MISSE 2 experiment in low Earth orbit the PPPA (Nomex) sample had an atomic oxygen erosion yield of 1.41e-24 cm3/atom, as listed in NASA TM-2008-215490.
best_for: 'Flame-resistant, high-temperature electrical and thermal insulation layers: continuous service to 220 °C and an LOI above 20.8 at 220 °C, as printed by DuPont'
weakest_at: 'Atomic oxygen in low Earth orbit: an erosion yield of 1.41e-24 cm3/atom on MISSE 2 means surface loss in orbit. Strength also falls with UV exposure and with heat ageing: about 65 % of breaking strength is kept after 1000 h at 260 °C'
identity:
  formula: Woven aramid fibre, poly(m-phenylene isophthalamide), meta-aramid; repeat unit C14H10N2O2
  molar_mass_repeat_unit: 238.2452 g/mol (NASA TM-2008-215490 Table II, PPPA row)
  monomers: 'm-phenylenediamine C6H8N2, 108.14 g/mol (PubChem CID 7935); isophthaloyl chloride C8H4Cl2O2, 203.02 g/mol (PubChem CID 7451); computed mass share in a 1:1 charge: 34.8 % m-phenylenediamine and 65.2 % isophthaloyl chloride'
  composition_by_mass: C 70.6 %, H 4.2 %, N 11.8 %, O 13.4 % of the repeat unit (computed from C14H10N2O2 with standard atomic weights)
  cas: ''
  source: dupont-nomex-characteristics
  where: DuPont characteristics page, Nomex 400 series; the MISSE 2 passport names the polymer as polyphenylene isophthalate (PPPA); repeat unit from NASA TM-2008-215490 Table II
tags:
  environments:
    - low-earth-orbit
  stresses:
    - atomic-oxygen
    - uv
    - total-radiation-dose
    - thermal-cycling
    - vacuum-and-outgassing
  applications:
    - habitats-and-suits
    - thermal-control
    - structures
    - electronics-and-chips
properties:
  - benchmark: atomic_oxygen_erosion_yield
    label: Atomic oxygen erosion yield, PPPA (Nomex), MISSE 2
    value: 1.41e-24
    unit: cm3/atom
    scope: material
    conditions:
      platform: ISS, MISSE 2 PEACE tray 1, low Earth orbit
      exposure: 2001-08-16 to 2005-07-30, AO fluence 8.43e21 atoms/cm2
    method: Measured on MISSE 2 flight samples and listed in NASA TM-2008-215490
    status: flight
    source: nasa-tm-2008-215490
    where: Table I, row PPPA (Nomex); value copied from the MISSE 2 passport, see review note
  - benchmark: dielectric_strength
    label: Short-term dielectric strength, densified Nomex 400 series
    value: 18
    value_high: 34
    unit: kV/mm
    scope: material
    conditions:
      form: densified Nomex 400 series paper and pressboard, depending on product type and thickness
      stress: short-term electrical stress
    method: Typical range printed on the DuPont characteristics page
    status: ground
    source: dupont-nomex-characteristics
    where: Electrical properties paragraph; printed as 18 kV/mm to 34 kV/mm (460 V/mil to 870 V/mil)
  - benchmark: continuous_service_temperature
    label: Continuous service temperature, Nomex 400 series
    value: 220
    unit: °C
    scope: material
    conditions:
      duration: at least 10 years of continuous exposure
      product: Nomex 400 series
    method: Value printed on the DuPont characteristics page
    status: ground
    source: dupont-nomex-characteristics
    where: Thermal properties paragraph; useful properties maintained for at least 10 years up to 220 °C
  - benchmark: limiting_oxygen_index
    label: Limiting oxygen index at 220 °C, Nomex 400 series
    value: 20.8
    unit: '%'
    scope: material
    conditions:
      temperature: 220 °C
      threshold: above 20.8 is the critical value for combustion in air
    method: Printed on the DuPont characteristics page; unit added from the LOI definition as a volume percent
    status: ground
    source: dupont-nomex-characteristics
    where: Flame resistance paragraph; printed as LOI at 220 °C above 20.8
  - benchmark: radiation_tolerance_dose
    label: Ionizing radiation before loss of useful properties, Nomex paper
    value: 800
    unit: Mrad
    scope: material
    conditions:
      equivalent: 8 MGy
      statement: essentially unaffected at this dose; retains useful properties after eight times this exposure
    method: Value printed on the DuPont characteristics page
    status: ground
    source: dupont-nomex-characteristics
    where: Radiation paragraph; printed as 800 megarads (8 Mgy)
  - benchmark: humidity_dielectric_retention
    label: Dielectric strength retained at 95 % relative humidity, densified Nomex
    value: 90
    unit: '%'
    scope: material
    conditions:
      humidity: 95 % relative humidity
      basis: share of bone-dry dielectric strength
      product: densified papers and pressboards
    method: Value printed on the DuPont characteristics page
    status: ground
    source: dupont-nomex-characteristics
    where: Moisture paragraph; printed as 90% of bone-dry dielectric strength
  - benchmark: density
    label: Density, Nomex 410 paper, 0.25 mm (10.2 mil)
    value: 0.96
    unit: g/cc
    scope: material
    conditions:
      form: Nomex 410 insulation paper, nominal 10 mil
      state: standard conditions, 23 C and 50 % RH
    method: Typical value per Arclin Nomex 410 datasheet, density row; the datasheet says values are typical and not specification limits
    status: ground
    source: arclin-nomex410
    where: Mechanical properties table, row Density, column 10.2 mil
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, machine direction, Nomex 410 paper 0.25 mm
    value: 296
    unit: N/cm
    scope: material
    conditions:
      form: Nomex 410 paper, nominal 10 mil
      direction: machine direction (MD)
    method: Typical value per ASTM D-828, Arclin Nomex 410 datasheet
    status: ground
    source: arclin-nomex410
    where: Mechanical properties table, row Tensile strength MD, column 10.2 mil
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, cross direction, Nomex 410 paper 0.25 mm
    value: 161
    unit: N/cm
    scope: material
    conditions:
      form: Nomex 410 paper, nominal 10 mil
      direction: cross direction (XD)
    method: Typical value per ASTM D-828, Arclin Nomex 410 datasheet
    status: ground
    source: arclin-nomex410
    where: Mechanical properties table, row Tensile strength XD, column 10.2 mil
  - benchmark: elongation
    label: Elongation, machine direction, Nomex 410 paper 0.25 mm
    value: 22
    unit: '%'
    scope: material
    conditions:
      form: Nomex 410 paper, nominal 10 mil
      direction: machine direction (MD)
    method: Typical value per ASTM D-828, Arclin Nomex 410 datasheet
    status: ground
    source: arclin-nomex410
    where: Mechanical properties table, row Elongation MD, column 10.2 mil
  - benchmark: shrinkage
    label: Shrinkage at 300 °C, machine direction, Nomex 410 paper 0.25 mm
    value: 0.4
    unit: '%'
    scope: material
    conditions:
      temperature: 300 °C
      form: Nomex 410 paper, nominal 10 mil
      direction: machine direction (MD)
    method: Value printed on the DuPont Nomex 410 datasheet (copy on spacematdb.com); the 2026 Arclin sheet does not print this row
    status: ground
    source: spacemat-nomex410
    where: Table III, row Shrinkage at 300 C MD, column 10 mil
  - benchmark: limiting_oxygen_index
    label: Limiting oxygen index at 220 °C, Nomex 410 paper
    value: 22
    value_high: 25
    unit: '%'
    scope: material
    conditions:
      temperature: 220 °C
      thickness: 0.05 to 0.76 mm, depending on thickness and density
    method: Printed on the DuPont Nomex 410 datasheet (copy on spacematdb.com), Figure 11 text
    status: ground
    source: spacemat-nomex410
    where: Chemical stability section, Limiting oxygen index paragraph; printed as 22 to 25 % at 220 °C
  - benchmark: limiting_oxygen_index
    label: Limiting oxygen index at room temperature, Nomex 410 paper
    value: 27
    value_high: 32
    unit: '%'
    scope: material
    conditions:
      temperature: room temperature
      thickness: depending on thickness and density
    method: Printed on the DuPont Nomex 410 datasheet (copy on spacematdb.com), Figure 11 text
    status: ground
    source: spacemat-nomex410
    where: Chemical stability section, Limiting oxygen index paragraph; printed as 27 to 32 % at room temperature
  - benchmark: tensile_strength_retention
    label: Tensile strength retained after electron radiation, Nomex 410 paper MD
    value: 65
    unit: '% of original'
    scope: material
    conditions:
      dose: 64 Mgy (6400 megarads) of 2 MeV electrons
      form: Nomex 410 paper, 0.25 mm, machine direction
    method: Table V of the DuPont Nomex 410 datasheet (copy on spacematdb.com); at 8 Mgy the MD value is 94 %
    status: ground
    source: spacemat-nomex410
    where: Table V, row Tensile strength MD, column 64 Mgy
  - benchmark: thermal_conductivity
    label: Thermal conductivity, Nomex 410 paper 0.25 mm, at 150 °C
    value: 139
    unit: mWatt/meter K
    scope: material
    conditions:
      temperature: 150 °C
      form: Nomex 410 paper, nominal 10 mil
    method: Table IV of the DuPont Nomex 410 datasheet, all data taken at 150 C
    status: ground
    source: spacemat-nomex410
    where: Table IV, row Thermal conductivity, column 10 mil
  - benchmark: density
    label: Density, Nomex Type 450 staple fibre
    value: 1.37
    unit: g/cm3
    scope: material
    conditions:
      product: Type 450 meta-aramid staple, 1.5 dpf, 32/2 CC
      state: as tested in the DuPont table
    method: Value printed in the DuPont Technical Guide for NOMEX Brand Fiber, Table II-1
    status: ground
    source: dupont-tech-guide
    where: Table II-1, row Density gm/cm3, column Type 450
  - benchmark: tenacity
    label: Tenacity, Nomex Type 450 staple yarn
    value: 2.9
    unit: gm/den
    scope: material
    conditions:
      product: Type 450 staple, 1.5 dpf, 32/2 CC spun yarn
      test: straight test, footnote 1 of Table II-1
    method: DuPont Technical Guide Table II-1 straight tenacity; tenacity is a grams-per-denier value, not a stress in MPa
    status: ground
    source: dupont-tech-guide
    where: Table II-1, Tensile properties, Tenacity row, column Type 450
  - benchmark: elongation
    label: Elongation at break, Nomex Type 450 staple yarn
    value: 22
    unit: '%'
    scope: material
    conditions:
      product: Type 450 staple, 1.5 dpf, 32/2 CC spun yarn
      test: straight test, footnote 1 of Table II-1
    method: DuPont Technical Guide Table II-1 straight test, elongation at break
    status: ground
    source: dupont-tech-guide
    where: Table II-1, Tensile properties, Elongation at break row, column Type 450
  - benchmark: cte
    label: Coefficient of linear expansion, Nomex fibre, 26 to 130 °C
    value: 0.000018
    unit: cm/cm-°C
    scope: material
    conditions:
      range: 26 to 130 C (78 to 266 F)
      product: Type 430, 450, 455, 462 and N301 fibres in the table
    method: Value printed in the DuPont Technical Guide Table II-1 (in/in F value 1.0e-5)
    status: ground
    source: dupont-tech-guide
    where: Table II-1, Coefficient of Linear Expansion row
  - benchmark: max_service_temp
    label: Maximum continuous operating temperature, Nomex fibre (hot-gas filtration)
    value: 204
    unit: °C
    scope: material
    conditions:
      basis: exposures lasting months to years, fibre form
      note: 400 F printed in the guide; this is a DuPont recommendation, not a test result
    method: Recommendation printed in the DuPont Technical Guide, Section II heat effects
    status: ground
    source: dupont-tech-guide
    where: Effect of Dry Heat section, paragraph on hot gas filtration; printed as 400 F (204 C)
  - benchmark: thermal_decomposition_onset
    label: Weight loss onset in air or nitrogen, Nomex Type 455 fibre (TGA)
    value: 400
    unit: °C
    scope: material
    conditions:
      atmosphere: air or nitrogen
      criterion: less than 10 % fibre weight loss up to this temperature
    method: Thermogravimetric analysis, Figure 2.5 text in the DuPont Technical Guide; rapid weight loss is seen above about 427 C
    status: ground
    source: dupont-tech-guide
    where: Effect of Dry Heat section, paragraph on TGA of Type 455 NOMEX; printed as approximately 752 F (400 C)
  - benchmark: tensile_strength_retention
    label: Breaking strength retained after heat ageing, Nomex fibre
    value: 65
    unit: '% of original'
    scope: material
    conditions:
      exposure: 1000 h in dry air at 260 C, then returned to room temperature
      form: fibre yarn
    method: DuPont Technical Guide, prolonged exposure to dry air at 500 F, stated as breaking strength and toughness about 65 % of the value before exposure
    status: ground
    source: dupont-tech-guide
    where: Effect of Dry Heat section, paragraph on prolonged exposure; printed as about 65 %
  - benchmark: tensile_strength_retention
    label: Strength retained after xenon-arc UV exposure, 200 denier Type 430 yarn
    value: 55
    unit: '% of original'
    scope: material
    conditions:
      exposure: 80 h xenon arc, AATCC Test Method 16E
      form: untwisted 200 denier Type 430 yarn
    method: Figure 2.14 of the DuPont Technical Guide; retention is about 70 % after 40 h; laboratory results do not correlate directly with garment life
    status: ground
    source: dupont-tech-guide
    where: UV Light section, Figure 2.14 text
  - benchmark: moisture_absorption
    label: Equilibrium moisture regain, NOMEX IIIA fabric
    value: 5
    value_high: 5.5
    unit: '%'
    scope: material
    conditions:
      condition: 70 F (21 C), 65 % RH, equilibrium
      test: ASTM D-2654
    method: Value printed in the DuPont Technical Guide, Moisture regain section
    status: ground
    source: dupont-tech-guide
    where: Moisture Regain and Dimensional Stability section; printed as 5 % to 5.5 %
  - benchmark: ultimate_tensile_strength
    label: Ultimate tensile strength, Nomex meta-aramid (general figure)
    value: 340
    unit: MPa
    scope: material
    conditions:
      basis: general figure for Nomex, orientation and test not stated
    method: Wikipedia Nomex Properties section states 340 MPa (49,000 psi); no test standard given
    status: ground
    source: wikipedia-nomex
    where: Properties section, first paragraph
corrosion:
  - environment: Ultraviolet light, xenon arc (laboratory, 200 denier Type 430 yarn)
    headline: Strength falls to about 55 % after 80 hours of xenon-arc exposure; colour changes first.
    effect: DuPont reports about 70 % of original strength after 40 h and about 55 % after 80 h. Discolouration (natural yarn to deep bronze) is not by itself a sign of fibre damage. Fabric of NOMEX III keeps about 70 % at 40 h and 50 % at 80 h, and its flame resistance is not affected.
    rating: moderate
    conditions:
      basis: laboratory xenon arc per AATCC 16E; DuPont says it cannot be correlated with garment life
      storage: DuPont advises dark storage and says window glass does not block the 360 nm band fully
    source: dupont-tech-guide
    where: UV Light section, Figures 2.14 and 2.15
  - environment: Heat ageing in dry air, 260 C for 1000 h
    headline: About 65 % of breaking strength is kept after 1000 h at 260 C.
    effect: After 1000 h at 260 C and return to room temperature, DuPont says breaking strength and toughness of Nomex fibre are about 65 % of the unaged value. For hot-gas filtration, a maximum continuous operating temperature of 204 C is recommended for exposures lasting months to years.
    rating: moderate
    conditions:
      basis: fibre yarn in dry air, prolonged exposure
    source: dupont-tech-guide
    where: Effect of Dry Heat section
  - environment: Electron radiation, 2 MeV beta, up to 64 Mgy (Nomex 410 paper)
    headline: Machine-direction tensile strength falls to 65 % and elongation to 18 % at 64 Mgy.
    effect: Table V of the DuPont datasheet gives tensile MD at 94 % and elongation MD at 76 % after 8 Mgy. At 64 Mgy the tensile MD is 65 %, elongation MD 18 %, and dielectric strength 31 kV/mm against 34 kV/mm unexposed.
    rating: low
    conditions:
      dose: 0 to 64 Mgy, 2 MeV electrons
    source: spacemat-nomex410
    where: Table V, radiation resistance table
  - environment: Atomic oxygen, low Earth orbit (MISSE 2 flight)
    headline: Measured erosion yield 1.41e-24 cm3/atom, above the predictive tool value of 1.03e-24.
    effect: NASA TM-2008-215490 Table VII lists the predicted yield for PPPA (Nomex) at 1.03e-24 cm3/atom and the MISSE 2 measured yield at 1.41e-24 cm3/atom. The predictive tool under-predicted erosion for this polymer.
    rating: moderate
    conditions:
      fluence: 8.43e21 atoms/cm2 (MISSE 2, 3.95 years)
    source: nasa-tm-2008-215490
    where: Table VII, row Polyphenylene isophthalate, PPPA (Nomex)
  - environment: Boiling water and hot wash
    headline: Boiling water shrinks Type 430 fibre by about 1.3 %, and repeated exposure adds to this.
    effect: DuPont reports immediate shrinkage of about 1.3 % in boiling water for Type 430, and a total of 3.8 % after 100 five-minute exposures. Type 450 staple has a printed maximum water shrinkage of 4.0 % at 100 C.
    rating: low
    conditions:
      basis: boiling water, fibre
    source: dupont-tech-guide
    where: Table II-1, row Shrinkage in water at 212 F (100 C); Moisture Regain and Dimensional Stability section
  - environment: Strong mineral acids and strong alkalis at elevated temperature
    headline: Acids and alkalis degrade the fibre; the effect rises with concentration, time and temperature.
    effect: DuPont Table II-3 rates 10 % hydrochloric acid at 21 C for 1000 h as an appreciable loss of 41 to 80 % of breaking strength. The guide says NOMEX resists acid solutions better than nylon, shows excellent resistance to alkalis at room temperature, but is degraded by strong alkalis at high temperatures.
    rating: moderate
    conditions:
      basis: table of specific concentration, temperature and time combinations, Type 430 filament yarn
    source: dupont-tech-guide
    where: Chemical Resistance section and Table II-3
  - environment: Common organic solvents (alcohols, ketones, acetone, toluene, xylene)
    headline: Slight softening and swelling, which is largely reversible when the solvent is removed.
    effect: Arclin states that common industrial solvents have a slight softening and swelling effect on Nomex 410 paper, similar to water, and that these effects are mainly reversible. DuPont says NOMEX fibre is highly resistant to most hydrocarbons and organic solvents.
    rating: low
    conditions:
      basis: solvent exposure at room temperature
    source: spacemat-nomex410
    where: Chemical stability section (DuPont text as copied on spacematdb.com); DuPont Technical Guide Chemical Resistance section
risks:
  hazards:
    - text: 'm-Phenylenediamine (monomer, CID 7935): PubChem aggregated GHS, Danger, lists H301 toxic if swallowed, H311 toxic in contact with skin, H331 toxic if inhaled, H317 may cause an allergic skin reaction, H319 serious eye irritation, H341 suspected of causing genetic defects, H400 and H410 very toxic to aquatic life. This describes the monomer, not the polymer.'
      ghs:
        - H301
        - H311
        - H317
        - H319
        - H331
        - H341
        - H400
        - H410
      source: pubchem-mpda
      where: Safety and Hazards, GHS Classification (aggregated), read in this run
    - text: 'Isophthaloyl chloride (monomer, CID 7451): PubChem aggregated GHS from 269 company reports, Danger, lists H314 severe skin burns and eye damage (95.5 % of reports), H312 harmful in contact with skin (99.6 %), H331 toxic if inhaled (71.7 %), and H318 serious eye damage (58 %). It hydrolyses to acid, so it is a corrosive acid chloride in the monomer stage.'
      ghs:
        - H312
        - H314
        - H318
        - H331
      source: pubchem-isophthaloyl-chloride
      where: Safety and Hazards, GHS Classification, ECHA C&L summary, read in this run
    - text: 'Finished Nomex fibre and paper: DuPont says finished products present no known adverse health or environmental effects, and that testing shows minimal risk. Burning gives CO2, water and oxides of nitrogen, with carbon monoxide and small amounts of hydrogen cyanide possible depending on conditions.'
      ghs: []
      source: dupont-tech-guide
      where: Section V Toxicology, Background and Toxicity
    - text: Residual dimethylacetamide (DMAC) from manufacture is present in the fibre, per DuPont. Surface finishes and additives are bound in the fibre and not a known hazard in handling or use.
      ghs: []
      source: dupont-tech-guide
      where: Section V Toxicology, Background
  failure_risks:
    - mode: Atomic oxygen erosion in low Earth orbit
      trigger: Exposure of an uncoated Nomex surface to atomic oxygen in low Earth orbit, as on the MISSE 2 flight
      consequence: Surface erosion at a yield of 1.41e-24 cm3/atom as measured on MISSE 2
      severity: moderate
      source: nasa-tm-2008-215490
      where: Table I
    - mode: Loss of strength from heat ageing
      trigger: Long exposure above the continuous service temperature, for example 1000 h at 260 C
      consequence: About 65 % of breaking strength is kept after 1000 h at 260 C (fibre), so margins must allow for the loss
      severity: moderate
      source: dupont-tech-guide
      where: Effect of Dry Heat section
    - mode: Colour change and strength loss from UV light
      trigger: Prolonged sunlight or artificial UV exposure of unprotected garments or fabric
      consequence: Natural yarn turns from light tone to deep bronze; strength falls to about 55 % after 80 h in xenon arc (yarn)
      severity: moderate
      source: dupont-tech-guide
      where: UV Light section
    - mode: Dimensional shrinkage in hot water or steam
      trigger: Boiling water or repeated hot wash, or steam with moisture and heat
      consequence: About 1.3 % shrinkage in one boiling exposure (Type 430), 3.8 % after 100 exposures
      severity: low
      source: dupont-tech-guide
      where: Moisture Regain and Dimensional Stability section
  side_effects:
    - text: Infrequent skin irritation on first wearing of new garments, from stiff unwashed fabric at binding points and seams (DuPont).
      source: dupont-tech-guide
      where: Dermatology section
  handling:
    - text: Keep garments and articles out of direct or indirect sunlight; store them in the dark. Incandescent light is preferable to fluorescent indoors, and storage near windows should be avoided (DuPont).
      source: dupont-tech-guide
      where: UV Light section, storage paragraph
    - text: Wash a new garment at least once before wearing, to remove mill stiffeners (DuPont).
      source: dupont-tech-guide
      where: Dermatology section
  mitigations:
    - text: In dry-type electrical use, keep continuous stress on Nomex 410 paper at or below 1.6 kV/mm (40 V/mil) to limit partial discharge risk, per Arclin.
      source: arclin-nomex410
      where: Electrical properties section
uses:
  - application: habitats-and-suits
    device: Extravehicular Mobility Unit Thermal Micrometeoroid Garment and ACES pressure suit
    example: Nomex was used for the Thermal Micrometeoroid Garment on the Extravehicular Mobility Unit, in conjunction with Kevlar and Gore-Tex, and in the ACES pressure suit, for fire and extreme environment protection including water immersion to near vacuum.
    source: wikipedia-nomex
    where: Applications section, U.S. space program paragraph
  - application: thermal-control
    device: Thermal blankets on the Space Shuttle Orbiter
    example: Nomex was used as thermal blankets on the payload bay doors, fuselage and upper wing surfaces of the Space Shuttle Orbiter.
    source: wikipedia-nomex
    where: Applications section, U.S. space program paragraph
  - application: structures
    device: Honeycomb core and laminate for aircraft construction
    example: Nomex paper saturated with phenolic resin is made into fireproof honeycomb structures, and honeycomb and mylar-Nomex laminates are used extensively in aircraft construction.
    source: wikipedia-nomex
    where: Applications section, first paragraph
  - application: habitats-and-suits
    device: Military pilot and aircrew flight suits
    example: Military pilots and aircrew wear flight suits made of over 92 percent Nomex to protect them from cockpit fires.
    source: wikipedia-nomex
    where: Applications section, firefighting and military paragraph
  - application: electronics-and-chips
    device: Electrical laminates, circuit boards and transformer cores
    example: Nomex paper is used in electrical laminates such as circuit boards and transformer cores, and is used for electrical insulation; Type 410 is the original and higher-volume paper grade.
    source: wikipedia-nomex
    where: Applications section, first paragraph; Production section
supply:
  - subject: Nomex meta-aramid fibre and paper
    abundance: Developed by DuPont in the early 1960s and first marketed in 1967 (Wikipedia). The Nomex 410 paper datasheet dated 04-2026 is issued under the Arclin name. No production volume or country share was read.
    producers:
      - name: DuPont
        note: Developed and first sold Nomex; the DuPont Nomex 410 datasheet is the older copy used for some values
        country: DuPont
      - name: Arclin
        note: Issues the current Nomex 410 technical data sheet (April 2026)
        country: Arclin
    critical_lists: []
    recycling: Not sourced.
    substitutes:
      - Kevlar (para-aramid) has higher tensile strength. Nomex strands cannot align during filament polymerisation and have less strength, per Wikipedia. Kevlar is often added to Nomex to improve tear resistance.
    source: wikipedia-nomex
    where: Production and Properties sections
  - subject: Other meta-aramid and aramid paper producers
    abundance: Named producers in Wikipedia. No share of world production is given.
    producers:
      - name: Teijin Aramid
        note: Teijinconex in the Netherlands and Japan
        country: Teijin Aramid
      - name: Toray
        note: Arawin in Japan
        country: Toray
      - name: Yantai Tayho
        note: New Star in China
        country: Yantai Tayho
      - name: SRO Group
        note: X-Fiper
        country: SRO Group
      - name: Kermel
        note: Meta-aramid variant made in France
        country: Kermel
      - name: Yantai Metastar Special Paper
        note: Aramid paper introduced in 2007
        country: Yantai Metastar Special Paper
    critical_lists: []
    recycling: Not sourced.
    substitutes: []
    source: wikipedia-aramid
    where: Meta-aramid trade names paragraph; Polymer preparation and paper paragraphs
media: []
documents:
  - title: DuPont, Characteristics of Nomex for insulation (web page)
    type: datasheet
    url: https://www.dupont.com/news/characteristics-of-nomex-for-insulation.html
  - title: Banks, de Groh and Backus, Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit, NASA/TM-2008-215490
    type: report
    url: https://ntrs.nasa.gov/citations/20090011780
    year: 2008
  - title: DuPont, Technical Guide for NOMEX Brand Fiber (copy hosted at nakedwhiz.com)
    type: datasheet
    url: https://www.nakedwhiz.com/gasketsafety/nomextechnicalguide.pdf
  - title: Arclin Nomex 410 technical data sheet (April 2026)
    type: datasheet
    url: https://arclin.com/wp-content/uploads/2026/04/Arclin%E2%84%A2-Nomex%C2%AE-410-Technical-Datasheet-04-2026.pdf
    year: 2026
  - title: DuPont Nomex Type 410 technical data sheet (copy hosted at spacematdb.com)
    type: datasheet
    url: https://www.spacematdb.com/spacemat/manudatasheets/nomex410.pdf
  - title: 'PubChem CID 7935: m-phenylenediamine (GHS classification)'
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/compound/7935
    year: 2026
  - title: 'PubChem CID 7451: isophthaloyl chloride (GHS classification)'
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/compound/7451
    year: 2026
gaps:
  - Fabric density (g/m2 for woven NOMEX fabric) and woven fabric tensile and tear were not read in this run. The fibre and paper values above are for Type 450 staple and Nomex 410 paper, not woven fabric.
  - The DuPont characteristics page values (220 C, LOI 20.8, 800 Mrad, 90 % humidity retention, dielectric 18 to 34 kV/mm) were carried over from the earlier run. That page was not re-read in this run, because its article returned only a request-processing placeholder.
  - The DuPont PDF and product URLs on dupont.com returned 404 pages in this run. The Technical Guide and Nomex 410 datasheet were read from third-party copies (nakedwhiz.com, spacematdb.com) and the current Arclin 410 sheet, so their version and date may differ from the DuPont originals.
  - 'LOI wording differs between sources: the DuPont guide prints 20.9 for the critical value and the DuPont web page 20.8. Both are kept as printed.'
  - Outgassing (TML, CVCM, WVR) for Nomex was not found in this run. No space-environment UV dose or atomic oxygen result exists here beyond the MISSE 2 erosion yield.
  - Feedstock and abundance for m-phenylenediamine and isophthaloyl chloride, country shares of Nomex or aramid production, and critical-mineral list entries were not found. No USGS or EU critical-minerals entry was read for these monomers.
  - The DuPont Safety Data Sheet for Nomex fibre and paper was not read. No GHS classification for the finished fibre or paper is recorded; the hazard rows above are for the monomers and the DuPont toxicology text.
  - CAS number for the polymer (poly(m-phenylene isophthalamide)) was not read in this run. The PubChem page for m-phenylenediamine lists a related polymer CAS only for a different polymer record.
  - Tensile strength values in the Arclin and spacemat copies differ at 10 mil (296 and 285 N/cm MD). The Arclin 2026 value is used; the older copy is cited for other rows.
  - 'Named custom property names used here, not in the canon: tenacity, thermal_decomposition_onset, and tensile_strength_retention (used for radiation, heat-ageing and UV retention). These are flagged here for the canon owner.'
  - Electron radiation is recorded as a retention table; no dose-response for the fibre or fabric was read, and the 800 Mrad DuPont figure is a qualitative claim.
  - The MISSE 2 passport value (1.41e-24) was checked against NASA TM-2008-215490 Table I and Table VII in this run; both print 1.41e-24 for PPPA (Nomex), with Table VII also giving a predicted 1.03e-24.
  - Recipe percentages are computed from the repeat unit formula C14H10N2O2 using standard atomic weights (C 12.011, H 1.008, N 14.007, O 15.999), which are not from a fetched page.
  - 'UV ageing data from the MDPI firefighter paper (doi 10.3390/polym14193948) was not read: the MDPI PDF request failed in this run. No other Nomex-specific UV ageing paper was read.'
sources:
  nasa-tm-2008-215490:
    title: Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit
    id: NASA/TM-2008-215490 (Banks, de Groh and Backus, December 2008), NTRS 20090011780
    url: https://ntrs.nasa.gov/citations/20090011780
    year: 2008
    kind: report
    license: NASA public document
  dupont-nomex-characteristics:
    title: DuPont, Characteristics of Nomex for insulation
    id: DuPont web page, Nomex 400 series characteristics
    url: https://www.dupont.com/news/characteristics-of-nomex-for-insulation.html
    year: 2026
    kind: datasheet
    license: manufacturer web page, linked not reproduced
  dupont-tech-guide:
    title: DuPont, Technical Guide for NOMEX Brand Fiber
    id: DuPont technical guide, fibre tables, UV, heat, moisture, chemical resistance and toxicology; copy hosted at nakedwhiz.com
    url: https://www.nakedwhiz.com/gasketsafety/nomextechnicalguide.pdf
    kind: datasheet
    license: manufacturer technical guide, linked not reproduced
  arclin-nomex410:
    title: Arclin Nomex 410 technical data sheet
    id: Arclin Nomex 410 technical data sheet, April 2026
    url: https://arclin.com/wp-content/uploads/2026/04/Arclin%E2%84%A2-Nomex%C2%AE-410-Technical-Datasheet-04-2026.pdf
    year: 2026
    kind: datasheet
    license: manufacturer datasheet, linked not reproduced
  spacemat-nomex410:
    title: DuPont Nomex Type 410 technical data sheet, copy hosted at spacematdb.com
    id: DuPont Nomex Type 410 datasheet, Tables I to V and LOI text; third-party copy
    url: https://www.spacematdb.com/spacemat/manudatasheets/nomex410.pdf
    kind: datasheet
    license: manufacturer datasheet copy, linked not reproduced
  wikipedia-nomex:
    title: Nomex, Wikipedia (properties, production, applications and history)
    id: en.wikipedia.org/wiki/Nomex
    url: https://en.wikipedia.org/wiki/Nomex
    kind: web
    year: 2026
    license: CC BY-SA 4.0
  wikipedia-aramid:
    title: Aramid, Wikipedia (meta-aramid producers and paper)
    id: en.wikipedia.org/wiki/Aramid
    url: https://en.wikipedia.org/wiki/Aramid
    kind: web
    year: 2026
    license: CC BY-SA 4.0
  pubchem-mpda:
    title: m-Phenylenediamine, PubChem CID 7935
    id: PubChem CID 7935 (CAS 108-45-2)
    url: https://pubchem.ncbi.nlm.nih.gov/compound/7935
    kind: database
    year: 2026
    license: public domain (NIH PubChem)
  pubchem-isophthaloyl-chloride:
    title: Isophthaloyl chloride, PubChem CID 7451
    id: PubChem CID 7451 (C8H4Cl2O2, 203.02 g/mol)
    url: https://pubchem.ncbi.nlm.nih.gov/compound/7451
    kind: database
    year: 2026
    license: public domain (NIH PubChem)
license: CC-BY-4.0
updated: '2026-10-19'
review:
  status: draft
  method: assistant
  checked_values: 25
  unreachable: 4
  caveats: 6
  note: 'Deepened by an AI assistant on 2026-10-19. Kept the six existing properties and the two existing sources. Added 19 properties from the Arclin Nomex 410 datasheet (April 2026), the DuPont Nomex 410 datasheet copy (spacematdb.com, Tables III to V and LOI text), the DuPont Technical Guide for NOMEX Brand Fiber (nakedwhiz.com copy, Table II-1 and Sections II, V), NASA TM-2008-215490 (Table I, Table II, Table VII), Wikipedia (Nomex, Aramid) and PubChem (CIDs 7935 and 7451). The NASA report was read via the NTRS PDF; the MISSE 2 value 1.41e-24 is confirmed in Table I and Table VII. Unreachable in this run: two dupont.com PDF URLs and a dupont.com product page returned 404 pages; the MDPI UV paper PDF failed. The DuPont web page for the Nomex 400 series returned no text and its values are carried over. Repeat unit and monomer shares are computed from formulas with standard atomic weights.'
story:
  recipe:
    line: 'Nomex is produced by condensation of the monomers m-phenylenediamine and isophthaloyl chloride (Wikipedia, Production). Each condensation step releases hydrogen chloride: C6H8N2 + C8H4Cl2O2 gives the repeat unit C14H10N2O2 and 2 HCl (formulas from PubChem, balance computed). The repeat unit has a molar mass of 238.2452, as printed for PPPA in NASA TM-2008-215490 Table II. The polymer is spun into fibre from a solution containing dimethylacetamide, and residual DMAC remains in the fibre (DuPont guide). Sheet is calendered paper made in a similar fashion (Wikipedia).'
    parts:
      - name: m-Phenylenediamine
        symbol: C6H8N2
        molar_mass: 108.14
        share_note: 34.8 percent of the monomer charge by mass (computed from 108.14 and 203.02 g/mol, 1:1 molar ratio)
        role: Diamine monomer; its two amine groups react with the acid chloride groups to build the amide links.
      - name: Isophthaloyl chloride
        symbol: C8H4Cl2O2
        molar_mass: 203.02
        share_note: 65.2 percent of the monomer charge by mass (computed from 108.14 and 203.02 g/mol, 1:1 molar ratio)
        role: Diacid chloride monomer; the chloride groups leave as HCl, one per amide bond.
      - name: Carbon
        symbol: C
        atoms: 14
        share_percent: 70.6
        role: About 71 % of the repeat unit by mass (computed from C14H10N2O2, standard atomic weights).
      - name: Hydrogen
        symbol: H
        atoms: 10
        share_percent: 4.2
        role: Aromatic and amide hydrogens of the repeat unit.
      - name: Nitrogen
        symbol: 'N'
        atoms: 2
        share_percent: 11.8
        role: Amide nitrogens of the repeat unit.
      - name: Oxygen
        symbol: O
        atoms: 2
        share_percent: 13.4
        role: Carbonyl oxygens of the amide groups.
  risk_groups:
    - title: For people
      lead: The DuPont page prints flame and heat properties for Nomex paper. The monomers carry GHS hazard codes, and the finished fibre has a low hazard profile according to DuPont.
      level: 1
      verdict: Monomer hazards read; finished fibre low risk per DuPont
      points:
        - label: Flame
          line: The LOI at 220 °C is above 20.8, the critical value for combustion in air.
        - label: Monomers
          line: PubChem lists m-phenylenediamine as toxic if swallowed, in contact with skin and if inhaled, and isophthaloyl chloride as causing severe skin burns and eye damage. Both are monomer hazards, not finished-product hazards.
        - label: Finished fibre
          line: DuPont says finished Nomex presents no known adverse health or environmental effects and minimal risk, with combustion products similar to those of wood.
    - title: If it fails
      lead: The failure routes in these sources are erosion in orbit, heat ageing and UV.
      points:
        - label: Atomic oxygen
          line: On MISSE 2 the PPPA (Nomex) erosion yield was 1.41e-24 cm3/atom, from NASA TM-2008-215490.
        - label: Heat and UV
          line: About 65 % of breaking strength is kept after 1000 h at 260 °C, and about 55 % after 80 h in xenon-arc UV (DuPont).
  why: Nomex is a meta-aramid, poly(m-phenylene isophthalamide). The DuPont page for the Nomex 400 series prints a continuous service temperature of 220 °C for at least 10 years and a radiation tolerance of 800 Mrad before its useful properties are essentially unaffected. DuPont developed it and it was adopted for race-car and firefighter clothing after fatal racing fires (Wikipedia).
  uses:
    - where: Space suits and spacecraft
      line: Nomex was used in the EMU thermal micrometeoroid garment and the ACES pressure suit, and as thermal blankets on the Space Shuttle Orbiter (Wikipedia).
    - where: Aircraft
      line: Honeycomb Nomex paper saturated with phenolic resin is used extensively in aircraft construction, and military flight suits are made of over 92 percent Nomex (Wikipedia).
    - where: Electronics
      line: Nomex paper is used in electrical laminates such as circuit boards and transformer cores (Wikipedia).
    - where: Fire and vehicle protection
      line: Firefighters, racing drivers and military crews wear Nomex clothing (Wikipedia).
  can_do:
    - label: Stay insulating at heat
      value: 220 °C continuous service
      benchmark: continuous_service_temperature
      line: Useful properties are maintained for at least 10 years of continuous exposure at temperatures up to 220 °C, as printed by DuPont for the paper.
    - label: Hold electrical strength
      value: 18 kV/mm to 34 kV/mm
      benchmark: dielectric_strength
      line: Short-term dielectric strength of densified Nomex papers and pressboards is printed as 18 kV/mm to 34 kV/mm, depending on product and thickness.
    - label: Survive in orbit
      value: 1.41e-24 cm3/atom
      benchmark: atomic_oxygen_erosion_yield
      line: The MISSE 2 flight sample of PPPA (Nomex) has an erosion yield of 1.41e-24 cm3/atom, as listed in NASA TM-2008-215490.
  compare: The DuPont values are for Nomex 400 series paper, and the erosion yield is for one flight sample, so the rows are examples and not a ranking. The Nomex 410 paper has a density of 0.96 g/cc and a machine-direction tensile strength of 296 N/cm at 10 mil, and its 220 °C limiting oxygen index is 22 to 25 %. The Type 450 fibre has a density of 1.37 g/cm3, a tenacity of 2.9 gm/den and an elongation of 22 %. Kevlar is stronger, since Nomex strands cannot align during polymerisation (Wikipedia).
  compare_rows:
    - scope: material
      label: Service temperature
      benchmark: continuous_service_temperature
    - scope: material
      label: Dielectric strength
      benchmark: dielectric_strength
    - scope: material
      label: Erosion yield
      benchmark: atomic_oxygen_erosion_yield
  handling:
    - Specify the product form, since the DuPont values are for densified paper and pressboard, not woven fabric.
    - Treat the DuPont values as printed typical values, not as specification limits.
    - Keep garments and articles in the dark, away from sunlight and window glass, and wash new garments once before wearing (DuPont).
  good_for:
    - 'Insulation layers at high temperature: continuous service to 220 °C for at least 10 years, per DuPont for the paper.'
    - 'Radiation-exposed insulation: useful properties kept to 800 Mrad (8 MGy), per DuPont.'
    - Flame-resistant crew clothing, thermal blankets and honeycomb structures, per Wikipedia and DuPont.
  watch_out:
    - Atomic oxygen erodes the surface at 1.41e-24 cm3/atom on MISSE 2, so exterior use needs protection or a rate allowance. The NASA predictive tool under-predicted this value (Table VII).
    - Fibre service temperature is recommended at 204 °C for long hot-gas exposure, below the 220 °C paper figure, and about 65 % of strength is kept after 1000 h at 260 °C.
    - 'UV light and sunlight reduce strength: about 55 % is kept after 80 h of xenon arc on yarn, and colour changes first (DuPont).'
    - Strong alkalis at high temperature degrade the fibre, and hot water shrinks it by about 1.3 % in one exposure (DuPont).
    - No outgassing, space UV or thermal-cycling result for Nomex was read in this run.
  verdict: Nomex is a meta-aramid with a continuous service temperature of 220 °C for paper, an LOI of 22 to 25 % at 220 °C, and about 65 % strength retained after 1000 h at 260 °C. In low Earth orbit it erodes at 1.41e-24 cm3/atom on MISSE 2, above the predictive tool's 1.03e-24. Fibre values now include density 1.37 g/cm3, tenacity 2.9 gm/den and elongation 22 %. Monomer hazards are sourced from PubChem; the finished-fibre SDS, feedstock and outgassing data are still missing.
