{ "spore": "profile", "id": "pi-cp1", "spore_version": "0.2", "family": "polyimides", "name": "Colorless polyimide CP1 film", "abbreviation": "PI (CP1)", "role": "flexible, optically clear polyimide film for thin-film space structures", "category": "polymers", "type": "polyimides", "summary": "CP1 is a colorless, fluorinated aromatic polyimide film developed at NASA Langley and now made under licence by NeXolve (formerly SRS Technologies). In MISSE 2 it eroded by atomic oxygen at 1.91e-24 cm3/atom, a little under Kapton HN at 2.81e-24. Under simulated space radiation it darkened far more than Kapton, with its solar absorptance rising by more than 0.3 without saturating. A 2 micrometre CP1 film with a vapour-deposited aluminum coating was deployed as a 20 square metre solar sail in 2005.\n", "best_for": "Thin, clear, flexible film for solar sails and sunshades where the film stays uncoated in orbit only for short times", "weakest_at": "Optical darkening under UV and particle radiation (solar absorptance rose more than 0.3 in simulation), and atomic-oxygen erosion of exposed film", "identity": { "formula": "C46H22O6N2F12 (repeat unit; fluorinated aromatic polyimide)", "designations": [], "source": "banks2008", "where": "Table IV (formula C46H22O6N2F12 and atomic mass 926.6656 g/mole for PI (CP1)); Table V lists 88 atoms per repeat unit, including 12 fluorine. Russell et al. (AIAA-2001-1414) state that all of the films tested are aromatic polyimides" }, "tags": { "environments": [ "low-earth-orbit" ], "stresses": [ "atomic-oxygen", "uv", "total-radiation-dose" ], "applications": [ "structures", "thermal-control" ] }, "properties": [ { "benchmark": "density", "label": "Density", "value": 1.4193, "bound": "exact", "unit": "g/cm3", "scope": "material", "conditions": { "specimen": "PI (CP1) polymer sample used in the MISSE 2 PEACE polymers experiment", "use": "density needed to convert mass loss into erosion yield" }, "method": "Density measurement made for the experiment and listed in the NASA report (which cites its references 11 and 12 for the experiment)", "status": "ground", "source": "banks2008", "where": "Table II (MISSE 2 PEACE polymers density and fractional ash content), column 'Density, ref. 12, rho'", "source_detail": { "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit", "id": "NASA/TM-2008-215490, NTRS 20090011780", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008, "kind": "report", "license": "public domain (NASA)" } }, { "benchmark": "atomic_oxygen_erosion_yield", "label": "Atomic oxygen erosion yield, MISSE 2 flight", "value": 1.91e-24, "bound": "exact", "unit": "cm3/atom", "scope": "material", "conditions": { "platform": "MISSE 2 PEACE polymers tray, ISS, outside the Quest airlock", "fluence": "8.43e21 atoms/cm2 (average of two fluence witness samples)", "exposure": "2001-08-16 to 2005-07-30, about 3.95 years" }, "method": "Mass loss divided by density and atomic oxygen fluence, as reported in the NASA predictive-tool report", "status": "flight", "source": "banks2008", "where": "Table I (MISSE 2 PEACE polymers erosion yield data), row PI (CP1); fluence from the text of section 2", "source_detail": { "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit", "id": "NASA/TM-2008-215490, NTRS 20090011780", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008, "kind": "report", "license": "public domain (NASA)" } }, { "benchmark": "predicted_atomic_oxygen_erosion_yield", "label": "Predicted atomic oxygen erosion yield", "value": 2.27e-24, "bound": "exact", "unit": "cm3/atom", "scope": "material", "conditions": { "model": "NASA predictive equation from the same report, fitted to the MISSE 2 data" }, "method": "Predicted value from the predictive tool. It is a model output, not a measurement", "status": "calculated", "source": "banks2008", "where": "Table VII (comparison of predicted and actual MISSE 2 erosion yields), row PI (CP1)", "source_detail": { "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit", "id": "NASA/TM-2008-215490, NTRS 20090011780", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008, "kind": "report", "license": "public domain (NASA)" } }, { "benchmark": "molar_mass", "label": "Molar mass of the repeat unit", "value": 926.6656, "bound": "exact", "unit": "g/mole", "scope": "material", "conditions": { "formula": "C46H22O6N2F12" }, "method": "Atomic mass of the repeat unit as printed in the NASA table", "status": "calculated", "source": "banks2008", "where": "Table IV (MISSE 2 PEACE polymers chemical structure), row PI (CP1)", "source_detail": { "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit", "id": "NASA/TM-2008-215490, NTRS 20090011780", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008, "kind": "report", "license": "public domain (NASA)" } }, { "benchmark": "volume_per_repeat_unit", "label": "Volume per repeat unit", "value": 1.08e-21, "bound": "exact", "unit": "cm3", "scope": "material", "conditions": { "basis": "volume per repeat unit calculated for the predictive tool" }, "method": "Calculated value from the predictive-tool data set, not a measured value", "status": "calculated", "source": "banks2008", "where": "Table IV, column 'Volume per repeat unit, V r', row PI (CP1)", "source_detail": { "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit", "id": "NASA/TM-2008-215490, NTRS 20090011780", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008, "kind": "report", "license": "public domain (NASA)" } }, { "benchmark": "minimum_volume_of_atoms", "label": "Minimum volume of atoms in the repeat unit", "value": 1.24e-22, "bound": "exact", "unit": "cm3", "scope": "material", "conditions": { "basis": "sum of atomic volumes in the repeat unit" }, "method": "Calculated value from the predictive-tool data set, not a measured value", "status": "calculated", "source": "banks2008", "where": "Table IV, column 'Minimum volume of atoms in repeat unit, V-Sigma', row PI (CP1)", "source_detail": { "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit", "id": "NASA/TM-2008-215490, NTRS 20090011780", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008, "kind": "report", "license": "public domain (NASA)" } }, { "benchmark": "ash_fraction", "label": "Fractional ash content", "value": 0.00171, "bound": "exact", "unit": "mass fraction", "scope": "material", "conditions": { "specimen": "PI (CP1) MISSE 2 PEACE polymers sample" }, "method": "Mass fraction of polymer that is ash, measured for the experiment", "status": "ground", "source": "banks2008", "where": "Table II, column 'Mass fraction of polymer that is ash, Na', row PI (CP1)", "source_detail": { "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit", "id": "NASA/TM-2008-215490, NTRS 20090011780", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008, "kind": "report", "license": "public domain (NASA)" } }, { "benchmark": "film_thickness", "label": "Film thickness of the uncoated flight sample", "value": 1, "bound": "exact", "unit": "mil", "scope": "material", "conditions": { "sample": "uncoated CP1, MISSE-1 and MISSE-2 flight samples in the NASA memo" }, "method": "Thickness as printed in the NASA memo (the sample description)", "status": "ground", "source": "ntrs2015", "where": "Section 3.1 (Uncoated Colorless Polyimide 1) and its figure 4 description", "source_detail": { "title": "NASA/TM-2015-218205: Analysis of Fluorinated Polyimides Flown on the Materials International Space Station Experiment", "id": "NASA/TM-2015-218205, NTRS 20150016168", "url": "https://ntrs.nasa.gov/citations/20150016168", "year": 2015, "kind": "report", "license": "public domain (NASA)" } }, { "benchmark": "atomic_oxygen_seam_failure_fluence", "label": "Atomic oxygen fluence at which the butt-joint seam failed", "value": 180000000000000000000, "bound": "exact", "unit": "atoms/cm2", "scope": "material", "conditions": { "sample": "1 mil uncoated CP1 with an adhesive-free butt-joint seam, MISSE-2", "exposure": "ISS, wake side, Kapton witness sample underneath" }, "method": "Seam failure detected by the Kapton witness sample underneath; the memo says the sample survived about 2e20 atoms/cm2 without a seam failure", "status": "flight", "source": "ntrs2015", "where": "Section 3.1, text on figure 4 (MISSE-2 uncoated CP1 with butt joint seam)", "source_detail": { "title": "NASA/TM-2015-218205: Analysis of Fluorinated Polyimides Flown on the Materials International Space Station Experiment", "id": "NASA/TM-2015-218205, NTRS 20150016168", "url": "https://ntrs.nasa.gov/citations/20150016168", "year": 2015, "kind": "report", "license": "public domain (NASA)" } }, { "benchmark": "solar_absorptance_increase", "label": "Increase in solar absorptance after simulated space radiation (CP film group)", "value": 0.3, "bound": "exact", "unit": "decimal (solar absorptance)", "scope": "material", "conditions": { "exposure": "simulated L1/L2 electron and proton radiation plus about 1000 equivalent solar hours UV, in vacuum", "films": "CP-1, CP-2 and TOR film samples as a group; the text says the increase was more than 0.3 without saturating" }, "method": "Solar absorptance computed from in situ reflectance measurements; the memo gives this as a lower bound for the group, not a value for CP1 alone", "status": "ground", "source": "russell2001", "where": "Results section, paragraph beginning 'The changes in solar absorptance from Kapton and Upilex samples remain less than 0.1'", "source_detail": { "title": "AIAA-2001-1414: Effects of Electrons, Protons, and Ultraviolet Radiation on Thermophysical Properties of Polymeric Films", "id": "AIAA-2001-1414, NTRS 20010072172", "url": "https://ntrs.nasa.gov/citations/20010072172", "year": 2001, "kind": "paper", "license": "public domain (NASA)" } }, { "benchmark": "solar_absorptance", "label": "Solar absorptance of colorless films before and after irradiation", "value": 0.2, "value_high": 0.5, "bound": "exact", "unit": "decimal (solar absorptance)", "scope": "material", "conditions": { "films": "colorless polyimide films (CP group), as a group", "exposure": "simulated L1/L2 radiation and UV, as printed in the text" }, "method": "Text summary of the solar absorptance change, read from the paper's results section; the paper gives the range as 'from about 0.2 to nearly 0.5'", "status": "ground", "source": "russell2001", "where": "Results section, paragraph on colorless films doubling their solar absorptance", "source_detail": { "title": "AIAA-2001-1414: Effects of Electrons, Protons, and Ultraviolet Radiation on Thermophysical Properties of Polymeric Films", "id": "AIAA-2001-1414, NTRS 20010072172", "url": "https://ntrs.nasa.gov/citations/20010072172", "year": 2001, "kind": "paper", "license": "public domain (NASA)" } }, { "benchmark": "infrared_emittance_change", "label": "Change in infrared emittance of CP-1 after combined UV, proton and electron exposure", "value": 8, "bound": "exact", "unit": "percent", "scope": "material", "conditions": { "exposure": "combined UV, proton and electron irradiation (simulated L1/L2 environment)", "measurement": "emittance measured in air, from about 0.47 to about 0.51 (decimal)" }, "method": "Text summary by the paper. Its figure is an increase of about eight percent in the measured emittance", "status": "ground", "source": "russell2001", "where": "Results section, paragraph beginning 'The thermal emittance values measured (in air) on the Kapton samples'", "source_detail": { "title": "AIAA-2001-1414: Effects of Electrons, Protons, and Ultraviolet Radiation on Thermophysical Properties of Polymeric Films", "id": "AIAA-2001-1414, NTRS 20010072172", "url": "https://ntrs.nasa.gov/citations/20010072172", "year": 2001, "kind": "paper", "license": "public domain (NASA)" } } ], "corrosion": [ { "environment": "Atomic oxygen in low Earth orbit", "headline": "Atomic oxygen erodes CP1 at about 1.91e-24 cm3 per atom, a little below Kapton HN.", "effect": "On MISSE 2 the PEACE polymers tray received 8.43e21 atoms/cm2 over about 3.95 years. The uncoated 1 mil CP1 film with a butt-joint seam survived about 2e20 atoms/cm2 on the wake side, but its seam failed at about 1.8e20, and the Kapton witness below showed the failure.", "rating": "severe", "conditions": { "flight_1": "MISSE 2 PEACE tray, 3.95 years, fluence 8.43e21 atoms/cm2", "flight_2": "MISSE-2 wake side, 1 mil butt-joint seam, seam failure at about 1.8e20 atoms/cm2" }, "source": "banks2008", "where": "Table I; the seam observation is from section 3.1 of ntrs2015" }, { "environment": "Space ultraviolet, protons and electrons (ground simulation)", "headline": "CP films darkened more than Kapton under simulated L1/L2 radiation, and their solar absorptance rose by more than 0.3 without saturating.", "effect": "The paper says the solar absorptance of CP and TOR films rose by more than 0.3 without saturating, while Kapton and Upilex stayed within 0.1. The text gives the CP group only; the per-material CP-1 numbers are in figures that were not converted to values here.", "rating": "severe", "conditions": { "exposure": "simulated five-year L1/L2 proton, electron and about 1000 equivalent solar hours of UV" }, "source": "russell2001", "where": "Results section, paragraph on in situ solar absorptance changes" }, { "environment": "Mechanical and thermal, as flown on MISSE", "headline": "No corrosion, ageing or thermal-cycling endurance value for CP1 film was read in a fetched source.", "effect": "The 2015 memo reports that uncoated CP1 showed no significant change in transmission on MISSE-1 and that its seam failed on MISSE-2. It gives no thermal-cycling or humidity result.", "rating": "unknown", "conditions": { "basis": "NASA memo section 3.1 (MISSE-1 and MISSE-2 uncoated CP1)" }, "source": "ntrs2015", "where": "Section 3.1, text on figure 3" } ], "risks": { "hazards": [], "failure_risks": [ { "mode": "Atomic oxygen erosion", "trigger": "Exposed CP1 film in low Earth orbit (MISSE 2 PEACE tray, 8.43e21 atoms/cm2)", "consequence": "Film thins and erodes; the MISSE 2 erosion yield was 1.91e-24 cm3/atom", "severity": "high", "source": "banks2008", "where": "Table I" }, { "mode": "Seam failure under atomic oxygen", "trigger": "1 mil uncoated CP1 with an adhesive-free butt-joint seam in MISSE-2 (about 1.8e20 atoms/cm2)", "consequence": "The butt joint failed while the film itself survived; a Kapton witness sample underneath showed the failure", "severity": "moderate", "source": "ntrs2015", "where": "Section 3.1, figure 4 text" }, { "mode": "Optical darkening under radiation and UV", "trigger": "Simulated L1/L2 electron, proton and UV exposure", "consequence": "Solar absorptance rose by more than 0.3 for the CP film group, and emittance rose by about eight percent for CP-1, with no sign of saturation", "severity": "high", "source": "russell2001", "where": "Results section" } ], "side_effects": [ { "text": "Erosion of an aluminized CP1 sample on MISSE-3 dropped its infrared emittance from 0.65 to 0.61 (the CP1 side was exposed).", "affects": "Thermal emittance of the film surface", "source": "ntrs2015", "where": "Section 3.2, text on figure 8" } ], "handling": [ { "text": "No handling or storage guidance for CP1 was found in a fetched source. No safety data sheet for CP1 was read.", "source": "ntrs2015", "where": "Not stated in the memo" } ], "mitigations": [ { "text": "Aluminum coating on one side of the film (vapour-deposited aluminum) was flown and used in the 2 micrometre solar sail. The memo does not give an erosion yield for the coated film.", "source": "ntrs2015", "where": "Section 8 and section 3.2" }, { "text": "A later modified grade, CORIN XLS, labelled as an AO-resistant CP1 and flown on MISSE-6A, had an atomic oxygen erosion yield of 8.4e-26 cm3/atom. It is not the same product as the original CP1 in this profile.", "source": "ntrs2015", "where": "Section 9 (CORIN XLS), page 22" } ] }, "uses": [ { "application": "structures", "device": "Solar sail made of 2 micrometre CP1 film with vapour-deposited aluminum", "example": "A 20 square metre sail was deployed under high vacuum at the Plum Brook Station test chamber in 2005 and led to the Nanosail-D2 mission in 2011. MISSE flight samples of the same film were flown behind windows on MISSE-6B.", "source": "ntrs2015", "where": "Section 8 (2-um CP1 with VDA solar sail), page 21 of the memo" }, { "application": "thermal-control", "device": "Thin-film sunshade for a deployable space telescope", "example": "The paper lists CP1 among thin-film candidates (12.5 micrometre films, vapour-deposited aluminum on one side) for a sunshade and solar sail in the Next Generation Space Telescope and Geomagnetic Storm Warning missions. It tested them for L1/L2 radiation and UV.", "source": "russell2001", "where": "Introduction, first two paragraphs and the film list" } ], "supply": [ { "subject": "Colorless polyimide CP1 film", "abundance": "Not read in a fetched source.", "producers": [ { "country": "United States (NeXolve in Huntsville, Alabama, per the NASA memo title page)" }, { "country": "United States" } ], "critical_lists": [], "recycling": "Not sourced.", "substitutes": [ "EP2550 (now Essar Stretch 255) is a low-modulus analog of CP1, visibly clear and easily modified with fillers, per the NASA memo." ], "source": "ntrs2015", "where": "Introduction (paragraph on NeXolve), section 3 (uncoated CP1 and CP1 variants) and the EP2550 description; manufacturer named in footnote 5 of AIAA-2001-1414 (russell2001)" } ], "media": [], "documents": [ { "title": "NASA/TM-2008-215490: Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit (Banks, Backus, de Groh)", "type": "report", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008 }, { "title": "AIAA-2001-1414: Effects of Electrons, Protons, and Ultraviolet Radiation on Thermophysical Properties of Polymeric Films (Russell et al.)", "type": "paper", "url": "https://ntrs.nasa.gov/citations/20010072172", "year": 2001 }, { "title": "NASA/TM-2015-218205: Analysis of Fluorinated Polyimides Flown on the Materials International Space Station Experiment (Finckenor, Rodman, Farmer)", "type": "report", "url": "https://ntrs.nasa.gov/citations/20150016168", "year": 2015 }, { "title": "Polyimide (Wikipedia)", "type": "database", "url": "https://en.wikipedia.org/wiki/Polyimide", "year": 2026 }, { "title": "NIST Atomic Weights and Isotopic Compositions: carbon, hydrogen, nitrogen, oxygen, fluorine", "type": "database", "url": "https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl", "year": 2026 } ], "gaps": [ "No glass transition, CTE, tensile, thermal-cycling or moisture-absorption value for CP1 was read in a fetched source. A vendor datasheet (Thermalbright, hybridplastics.com) was not reachable in this run, so none is entered.", "No safety data sheet, PubChem record or GHS classification for CP1 was found; the hazards list is empty.", "The monomers of CP1 are not named in a fetched source; the recipe lists only the repeat unit and NIST atomic weights.", "Supply abundance, country shares, critical-mineral lists and recycling were not read in a fetched source.", "The MISSE 2 erosion value (1.91e-24) is for the PEACE polymers tray at the ISS fluence of 8.43e21 atoms/cm2 in Banks 2008. The 2015 NASA memo gives a wake-side MISSE-2 fluence of 1.7 to 2e20 atoms/cm2 for a separate 1 mil uncoated sample; the two exposures are not the same, and we have not reconciled them.", "The CP film solar absorptance change is for the CP group (CP-1, CP-2, TOR), read from text. Per-material CP-1 values are in bar and line graphs in AIAA-2001-1414 and were not converted to numbers.", "Non-canonical property names: atomic_oxygen_seam_failure_fluence, minimum_volume_of_atoms, infrared_emittance_change and solar_absorptance_increase are not in property-canon.yaml.", "Recipe monomers, process and imidisation conditions for CP1 are not in any fetched source. The Wikipedia page describes polyimides in general only." ], "story": { "why": "CP1 is a colorless, fluorinated polyimide from NASA Langley. The NIST atomic weights and the NASA repeat-unit formula give a molar mass of 926.6656 g/mole. It was made for thin, clear film that can be used in space, and the flight data show that it survives on MISSE 2 but erodes and darkens under atomic oxygen and radiation. The erosion yield, 1.91e-24 cm3/atom, is lower than Kapton HN (2.81e-24) in the same NASA table.", "uses": [ { "where": "2-micrometre solar sail (Plum Brook test, 2005; Nanosail-D2, 2011)", "line": "A 20 square metre sail of 2 micrometre CP1 with vapour-deposited aluminum was deployed in vacuum. The memo says this led to the Nanosail-D2 mission." }, { "where": "Thin-film sunshade candidates", "line": "CP1 is one of the thin-film candidates for a sunshade in the Next Generation Space Telescope, tested for L1/L2 radiation and UV." } ], "can_do": [ { "label": "Atomic oxygen", "line": "On MISSE 2 the CP1 film eroded at 1.91e-24 cm3/atom, lower than Kapton HN at 2.81e-24.", "scope": "material", "value": "1.91e-24 cm3/atom" }, { "label": "Density", "line": "Density of the MISSE 2 CP1 sample in the NASA table.", "scope": "material", "value": "1.4193 g/cm3" }, { "label": "Radiation", "line": "Simulated L1/L2 radiation and UV raised the solar absorptance of the CP film group by more than 0.3 without saturating.", "scope": "material", "value": "More than 0.3 solar absorptance rise" }, { "label": "Solar sail", "line": "A 2 micrometre CP1 sail of 20 square metres was deployed in vacuum at GRC in 2005.", "scope": "material", "value": "20 square metres" } ], "compare": "In the same MISSE 2 table, CP1 eroded at 1.91e-24 cm3/atom against 2.81e-24 for Kapton HN. Under simulated space radiation the CP films darkened by more than 0.3, while Kapton and Upilex stayed within 0.1 (russell2001). The fetched sources give no CP1 comparison with metals or composites.", "compare_rows": [ { "label": "Density", "benchmark": "density", "scope": "material" }, { "label": "Atomic oxygen erosion yield", "benchmark": "atomic_oxygen_erosion_yield", "scope": "material" }, { "label": "Solar absorptance rise under radiation", "benchmark": "solar_absorptance_increase", "scope": "material" } ], "handling": [ "No handling or storage guidance for CP1 was found in a fetched source.", "Keep the film out of atomic oxygen unless it is covered or coated, since the seam and the surface both erode." ], "good_for": [ "Thin, clear, flexible film for solar sails and sunshades. The 2 micrometre sail deployed in vacuum on the ground.", "Flight-proven film with a MISSE 2 erosion yield (1.91e-24 cm3/atom) lower than Kapton HN." ], "watch_out": [ "Atomic oxygen erosion. The MISSE 2 erosion yield is 1.91e-24 cm3/atom, and the seam of a 1 mil sample failed at about 1.8e20 atoms/cm2.", "Radiation darkening. The CP film group gained more than 0.3 solar absorptance in simulation, without saturating.", "Commercial grades differ. NeXolve adds proprietary additives and coatings to CP1, so the values here may not match a current product." ], "verdict": "CP1 is a clear, thin, flexible polyimide that was flown on MISSE 2 and used in a 2 micrometre solar sail. It erodes under atomic oxygen (1.91e-24 cm3/atom) and darkens more than Kapton under simulated radiation, so exposed film needs a cover or coating. The record is thin: no CP1 thermal, mechanical or hazard data were read, and the gaps below list them.", "recipe": { "line": "Repeat unit C46H22O6N2F12, molar mass 926.6656 g/mole (Banks 2008, Table IV). It is a fluorinated aromatic polyimide, so it is made from a dianhydride and a diamine that form a poly(amic acid), which is then cyclised to the polyimide. The fetched Wikipedia page describes this two-step route for polyimides in general and does not name CP1's monomers, so the specific monomers are not listed here.", "parts": [ { "name": "Carbon", "symbol": "C", "role": "Carbon backbone of the aromatic rings and imide groups (NIST standard atomic weight interval)." }, { "name": "Hydrogen", "symbol": "H", "role": "Hydrogen on the aromatic rings (NIST standard atomic weight interval)." }, { "name": "Oxygen", "symbol": "O", "role": "Imide carbonyl and ether oxygens (NIST standard atomic weight interval)." }, { "name": "Nitrogen", "symbol": "N", "role": "Imide nitrogens (NIST standard atomic weight interval)." }, { "name": "Fluorine", "symbol": "F", "role": "Fluorine groups that make the film colorless and clear (per the NASA memo's description of CP1 as visibly clear); the NASA table does not say which bonds carry them.", "atoms": 12, "atomic_weight": 18.9984031636 } ] }, "risk_groups": [ { "title": "For people", "lead": "No safety data sheet for CP1 was read, so no hazard statement is recorded here.", "points": [ { "label": "Hazard data", "line": "None found in a fetched source. The DuPont sheet for Kapton does not apply to CP1." } ], "level": 1, "verdict": "No hazard classification found in a fetched source" }, { "title": "If it fails", "lead": "These results come from flight exposure of uncoated film and from a laboratory simulation.", "points": [ { "label": "Atomic oxygen", "line": "Erosion yield 1.91e-24 cm3/atom on MISSE 2, and the seam of a 1 mil sample failed at about 1.8e20 atoms/cm2." }, { "label": "Radiation darkening", "line": "CP film solar absorptance rose by more than 0.3 in simulation." } ] }, { "title": "Handling and storage", "points": [ { "label": "Storage", "line": "No storage guidance found in a fetched source." } ] } ] }, "updated": "2026-10-20", "review": { "status": "draft", "method": "assistant", "checked_values": 12, "unreachable": 1, "caveats": 4, "note": "Written by an AI assistant on 2026-10-20. Values were read from text extracted from NASA/TM-2008-215490 (Banks 2008) and NASA/TM-2015-218205 (2015), from the text and tables of AIAA-2001-1414 (Russell 2001), and from the Wikipedia Polyimide page and NIST atomic weight pages, all fetched in this run. Caveats: the MISSE 2 fluence differs between the Banks report and the 2015 memo; the CP film solar absorptance values are group values read from text; no CP1 datasheet or safety sheet was reached; the monomers of CP1 are unnamed in the sources read." }, "sources": { "banks2008": { "title": "Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit", "id": "NASA/TM-2008-215490, NTRS 20090011780", "url": "https://ntrs.nasa.gov/citations/20090011780", "year": 2008, "kind": "report", "license": "public domain (NASA)" }, "russell2001": { "title": "AIAA-2001-1414: Effects of Electrons, Protons, and Ultraviolet Radiation on Thermophysical Properties of Polymeric Films", "id": "AIAA-2001-1414, NTRS 20010072172", "url": "https://ntrs.nasa.gov/citations/20010072172", "year": 2001, "kind": "paper", "license": "public domain (NASA)" }, "ntrs2015": { "title": "NASA/TM-2015-218205: Analysis of Fluorinated Polyimides Flown on the Materials International Space Station Experiment", "id": "NASA/TM-2015-218205, NTRS 20150016168", "url": "https://ntrs.nasa.gov/citations/20150016168", "year": 2015, "kind": "report", "license": "public domain (NASA)" }, "wiki-polyimide": { "title": "Polyimide (Wikipedia)", "id": "en.wikipedia.org/wiki/Polyimide", "url": "https://en.wikipedia.org/wiki/Polyimide", "year": 2026, "kind": "web", "license": "CC BY-SA" }, "nist-c": { "title": "NIST Atomic Weights and Isotopic Compositions: carbon", "id": "NIST standard atomic weights, C (Z=6): 12.0096 to 12.0116", "url": "https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=C&ascii=html", "year": 2026, "kind": "database", "license": "public domain (US government)" }, "nist-h": { "title": "NIST Atomic Weights and Isotopic Compositions: hydrogen", "id": "NIST standard atomic weights, H (Z=1): 1.00784 to 1.00811", "url": "https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=H&ascii=html", "year": 2026, "kind": "database", "license": "public domain (US government)" }, "nist-n": { "title": "NIST Atomic Weights and Isotopic Compositions: nitrogen", "id": "NIST standard atomic weights, N (Z=7): 14.00643 to 14.00728", "url": "https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=N&ascii=html", "year": 2026, "kind": "database", "license": "public domain (US government)" }, "nist-o": { "title": "NIST Atomic Weights and Isotopic Compositions: oxygen", "id": "NIST standard atomic weights, O (Z=8): 15.99903 to 15.99977", "url": "https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=O&ascii=html", "year": 2026, "kind": "database", "license": "public domain (US government)" }, "nist-f": { "title": "NIST Atomic Weights and Isotopic Compositions: fluorine", "id": "NIST standard atomic weights, F (Z=9): 18.998403163(6)", "url": "https://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=F&ascii=html", "year": 2026, "kind": "database", "license": "public domain (US government)" } }, "license": "CC-BY-4.0", "url": "https://spacemushroom.com/profiles/pi-cp1/" }