spore: profile id: pi-upilex-s spore_version: 0.2 family: polyimides name: Upilex-S polyimide film (BPDA) abbreviation: PI (Upilex-S) role: flexible insulating film category: polymers type: polyimides summary: | Upilex-S is UBE's standard polyimide film, made from biphenyl tetracarboxylic dianhydride (BPDA) rather than the pyromellitic dianhydride used in Kapton. The UBE datasheet gives a tensile strength of 520 MPa and a density of 1.47 (x10^3 kg/m3) for 25 micrometre film at 25 degC. In low Earth orbit on MISSE 2 the film eroded at 9.22e-24 cm3/atom, about three times the Kapton HN rate in the same NASA table, so exposed Upilex-S needs a cover. The NASA erosion yield is from one flight record and the UBE values come from a manufacturer datasheet; no finished part was flown. best_for: A thin, flexible, electrically insulating film with a very low coefficient of thermal expansion and no melting point, where dimensional stability over temperature matters more than atomic-oxygen resistance weakest_at: Atomic-oxygen erosion in low Earth orbit (MISSE 2 erosion yield 9.22e-24 cm3/atom, the highest of the polyimides in the NASA table), so exposed film must be covered or coated identity: formula: C22H10O4N2 (repeat unit, from NASA Table IV); BPDA-based polyimide cas: '' source: banks2008 where: Table IV lists PI (Upilex-S) with formula C22H10O4N2 and molecular weight 366.3320; NASA Table V gives the atom counts. The CAS number is not read in this run and is left blank. tags: environments: - low-earth-orbit stresses: - atomic-oxygen - uv - total-radiation-dose - thermal-cycling - vacuum-and-outgassing applications: - electronics-and-chips - thermal-control properties: - benchmark: density label: Density (measured, MISSE 2 sample) value: 1.3866 unit: g/cm3 scope: material conditions: sample: MISSE 2 PEACE Polymers film, dehydrated before measurement temperature: not stated unit_in_source: g/cm3 method: Measured density reported by NASA (ref. 12 density method) status: ground source: banks2008 where: Table II, density column for PI (Upilex-S or US), value printed as 1.3866 g/cm3 - benchmark: density label: Density (datasheet, 25 um film) value: 1.47 unit: x10^3 kg/m3 scope: material conditions: product: UPILEX-25S film, 25 micrometre temperature: 25 degC unit_in_source: x10^3 kg/m3 method: ASTM D1505, as printed in the UBE datasheet status: ground source: ube_upilex_s where: Section (1) Mechanical properties, Density row; also repeated in Section (5) as 1.47 for UPILEX-25S - benchmark: ultimate_tensile_strength label: Tensile strength at 25 degC value: 520 unit: MPa scope: material conditions: product: UPILEX-25S temperature: 25 degC film_thickness: 25 micrometre method: ASTM D882 status: ground source: ube_upilex_s where: Section (1) Mechanical properties, Tensile strength row, 25 degC column for UPILEX-25S - benchmark: ultimate_tensile_strength label: Tensile strength at 300 degC value: 290 unit: MPa scope: material conditions: product: UPILEX-25S temperature: 300 degC method: ASTM D882 status: ground source: ube_upilex_s where: Section (1) Mechanical properties, Tensile strength row, 300 degC column for UPILEX-25S - benchmark: ultimate_tensile_strength label: Tensile strength at -269 degC value: 740 unit: MPa scope: material conditions: product: UPILEX-25S temperature: '-269 degC' method: ASTM D882 status: ground source: ube_upilex_s where: Section (1) Mechanical properties, Tensile strength row, -269 degC column for UPILEX-25S - benchmark: elongation label: Elongation at 25 degC value: 40 unit: '%' scope: material conditions: product: UPILEX-25S temperature: 25 degC method: ASTM D882 status: ground source: ube_upilex_s where: Section (1) Mechanical properties, Elongation row, 25 degC column for UPILEX-25S - benchmark: elastic_modulus label: Tensile modulus at 25 degC value: 9.1 unit: GPa scope: material conditions: product: UPILEX-25S temperature: 25 degC method: ASTM D882 status: ground source: ube_upilex_s where: Section (1) Mechanical properties, Tensile modulus row, 25 degC column for UPILEX-25S - benchmark: cte label: Thermal linear expansion coefficient (50 to 200 degC) value: 12 unit: ppm/degC scope: material conditions: product: UPILEX-25S temperature_range: 50 to 200 degC heating_rate: 5 degC/min method: Fine linear dilatometer status: ground source: ube_upilex_s where: Section (3) Thermal properties, Thermal linear expansion coefficient row, UPILEX-25S column - benchmark: heat_shrinkage label: Heat shrinkage value: 0.05 unit: '%' scope: material conditions: product: UPILEX-25S temperature: 200 degC time: 2 h method: ASTM D1204 status: ground source: ube_upilex_s where: Section (3) Thermal properties, Heat shrinkage row, UPILEX-25S column - benchmark: specific_heat label: Specific heat value: 1.13 unit: kJ/(kg.K) scope: material conditions: product: UPILEX film (grade not stated in the row) temperature: not stated method: Differential scanning calorimeter status: ground source: ube_upilex_s where: Section (3) Thermal properties, Specific heat row - benchmark: thermal_conductivity label: Thermal conductivity (thickness direction) value: 0.29 unit: W/(m.K) scope: material conditions: product: UPILEX-S film (grade not stated in the row) direction: thickness method: Laser flash method status: ground source: ube_upilex_s where: Section (3) Thermal properties, Thermal conductivity row - benchmark: heat_life_temperature label: Heat life (tensile strength basis, 20,000 h) value: 290 unit: degC scope: material conditions: product: UPILEX-S film (grade not stated in the row) time: 20000 h method: Fixed temperature method, tensile strength basis as printed status: ground source: ube_upilex_s where: Section (3) Thermal properties, Heat life (Tensile strength) row - benchmark: oxygen_index label: Oxygen index value: 66 unit: '%' scope: material conditions: product: UPILEX-S film (grade not stated in the row) method: JIS K7201 status: ground source: ube_upilex_s where: Section (3) Thermal properties, Oxygen index row - benchmark: dielectric_strength label: Dielectric strength at 25 degC value: 6.8 unit: kV scope: material conditions: product: UPILEX-25S temperature: 25 degC frequency: 60 Hz method: ASTM D149 status: ground source: ube_upilex_s where: Section (2) Electrical properties, Dielectric strength row, UPILEX-25S 25 degC - benchmark: dielectric_constant label: Dielectric constant at 25 degC value: 3.5 unit: '-' scope: material conditions: product: UPILEX-25S temperature: 25 degC frequency: 1 kHz method: ASTM D150 status: ground source: ube_upilex_s where: Section (2) Electrical properties, Dielectric constant row, 1kHz, 25 degC - benchmark: dissipation_factor label: Dissipation factor at 25 degC value: 0.0013 unit: '-' scope: material conditions: product: UPILEX-25S temperature: 25 degC frequency: 1 kHz method: ASTM D150 status: ground source: ube_upilex_s where: Section (2) Electrical properties, Dissipation factor row, 1kHz, 25 degC - benchmark: moisture_absorption label: Water absorption (23 degC, 24 h immersion) value: 1.4 unit: '%' scope: material conditions: temperature: 23 degC time: 24 h condition: water immersion method: ASTM D570 status: ground source: ube_upilex_s where: Section (4) Chemical-resistant properties, Water absorption row, 23 degC 24h water immersion - benchmark: atomic_oxygen_erosion_yield label: Atomic oxygen erosion yield (LEO, MISSE 2) value: 9.22e-24 unit: cm3/atom scope: material status: flight conditions: environment: low Earth orbit, ISS, MISSE 2 PEACE tray (outside Quest airlock) atomic_oxygen_fluence: 8.43e21 atoms/cm2 exposure_duration: about 4 years (2001 to 2005) method: Mass loss with carefully dehydrated mass measurement, density from Table II, erosion yield per NASA TM-2008-215490 source: banks2008 where: Table I, MISSE 2 PEACE polymers erosion yield, row PI (Upilex-S or US); fluence from section 2.1 - benchmark: ash_content label: Ash content (mass fraction, Na) value: 0.000482 unit: '-' scope: material conditions: sample: MISSE 2 PEACE Polymers film method: RF plasma asher, as described in NASA TM-2008-215490 status: ground source: banks2008 where: Table II, mass fraction of polymer that is ash, row PI (Upilex-S or US) corrosion: - environment: Low Earth orbit atomic oxygen (ISS, MISSE 2) headline: Atomic oxygen erodes Upilex-S at 9.22e-24 cm3/atom, the highest erosion yield among the polyimides in the NASA MISSE 2 table. effect: Over the MISSE 2 flight the polymer lost material at 9.22e-24 cm3/atom. For comparison, the NASA table gives 3.00e-24 for Kapton H and 2.81e-24 for Kapton HN. Exposed film must be covered or coated. rating: severe conditions: fluence: 8.43e21 atoms/cm2 duration: about 4 years source: banks2008 where: Table I row PI (Upilex-S or US); Table I rows PI (Kapton H) and PI (Kapton HN); section 2.1 - environment: Solar and charged-particle exposure (MISSE 2) headline: NASA's ground-simulation comparison covers Upilex-S, but no Upilex-S absorptance number was read in this run. effect: NASA's comparison of proton, electron and ultraviolet simulation discusses Kapton and Upilex S together; the Upilex-S absorptance change is not reproduced here. rating: low conditions: exposure: ISS MISSE 2, total equivalent sun hours 5000 to 6700 ESH source: banks2008 where: Section 2.1 (equivalent sun hours); the solar absorptance comparison is not reproduced here - environment: Chemical bath (acids, alkalis, hot water) headline: Strength falls to 80 percent after 5 days in 10 percent sodium hydroxide at 25 degC; hot water barely changes the film. effect: UBE reports strength retention of 80 percent in 10% sodium hydroxide, 25 degC, 5 days immersion, and 95 percent in pH 1.0 water at 100 degC for 2 weeks. The datasheet says the film is insoluble in organic solvents and resists virtually all chemicals. rating: low conditions: product: UPILEX-25S test: ASTM D882 retention after immersion source: ube_upilex_s where: Section (4) Chemical-resistant properties, strength retention table risks: hazards: - text: Heated above 300 degC, the film gives off traces of residual DMAC, which forms carbon monoxide; above 500 degC it gives pyrolytic products. UBE advises ventilation so DMAC stays below 10 ppm and carbon monoxide below 100 ppm, and organic gas masks for fume exposure. ghs: [] source: ube_upilex_s where: Section (6) Packing and handling precautions, handling note - text: UBE says the film is flame resistant (UL94 V-0, oxygen index 66 percent) but advises checking the supplier safety data sheet before use. ghs: [] source: ube_upilex_s where: Section (3) Thermal properties, flammability row; Section (6) handling note failure_risks: - source: banks2008 where: Table I mode: Atomic oxygen in low Earth orbit removes the film at 9.22e-24… consequence: Atomic oxygen in low Earth orbit removes the film at 9.22e-24 cm3/atom, so bare Upilex-S film does not survive a long LEO mission. side_effects: [] handling: - text: Use good ventilation when heating the film, because of residual DMAC and pyrolysis products above 300 degC. source: ube_upilex_s where: Section (6) handling precautions mitigations: - text: Cover or coat the film in LEO. The erosion yield in the NASA table is the reason; no cover or coating was tested in the fetched sources. source: banks2008 where: Table I uses: - application: electronics-and-chips device: Flexible printed circuit and TAB-tape substrates example: UBE says Upilex-S changes little in size when heated, which suits minute circuits in flexible printed circuit and TAB-tape substrates. source: ube_upilex_s where: Section (3) Thermal properties, intro paragraph - application: thermal-control device: Carrier base and release film for high-temperature processing example: UBE lists Upilex-S as a carrier base and releasing material because its outgassing is low. source: ube_upilex_s where: Section (6) Smooth surface, application examples - application: electronics-and-chips device: Electrical insulation in high-temperature circuits example: UBE says the electrical properties hardly change at 200 degC, with a dielectric strength of 6.8 kV at 25 degC and 60 Hz. source: ube_upilex_s where: Section (2) Electrical properties supply: - subject: Polyimide film (Upilex) abundance: Monomer feedstock abundance was not read in a fetched page. producers: - name: UBE Corporation note: Makes UPILEX polyimide film from BPDA monomers (UBE datasheet) country: Japan critical_lists: [] recycling: Not sourced. source: ube_upilex_s where: 'Cover page: UBE''s BPDA monomer and UPILEX film grades' gaps: - Atomic oxygen erosion for Upilex-S is one MISSE 2 flight value; the NASA predicted-vs-measured table (Table VII) prints 9.22e-25 for Upilex-S, which conflicts with Table I (9.22e-24). Table I is used here; the conflict is not resolved. - Glass transition temperature for Upilex-S was not found in any fetched page. - Density for the UBE datasheet row is printed as x10^3 kg/m3; the value is kept as printed and not converted. - Supply country shares, production volumes and critical-mineral lists were not reached in this run. - Hazard classification (GHS) and the supplier SDS were not read in this run. - Story media and outgassing (NASA Goddard database) were not read in this run. - Only three sources were reached in this run; the lithium standard asks for eight. sources: banks2008: title: 'NASA/TM-2008-215490: Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit (Banks, Backus, de Groh)' id: NASA/TM-2008-215490 url: https://ntrs.nasa.gov/citations/20090011780 year: 2008 kind: report license: public domain (US government work) ube_upilex_s: title: UBE UPILEX-S polyimide film datasheet (English) id: ube.com/upilex/catalog/pdf/upilex_s_e.pdf url: https://ube.com/upilex/catalog/pdf/upilex_s_e.pdf kind: datasheet license: manufacturer document, linked not reproduced wiki_polyimide: title: 'Wikipedia: Polyimide (composition and history only)' id: en.wikipedia.org/wiki/Polyimide url: https://en.wikipedia.org/wiki/Polyimide kind: web license: CC-BY-SA-4.0 documents: - title: 'NASA/TM-2008-215490: Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit' type: report url: https://ntrs.nasa.gov/citations/20090011780 year: 2008 - title: UBE UPILEX-S polyimide film datasheet type: datasheet url: https://ube.com/upilex/catalog/pdf/upilex_s_e.pdf license: CC-BY-4.0 updated: '2026-10-20' review: status: draft method: assistant checked_values: 19 unreachable: 6 caveats: 3 note: Written by an AI assistant on 2026-10-20 from text extracted from the NASA TM-2008-215490 PDF and the UBE Upilex-S datasheet PDF, both fetched in this run. Wikipedia was read for composition and history only. Only three sources were reached; the rest of the lithium standard is listed in gaps. story: risk_groups: - title: Electronics and space engineers who need a thin, insulating film… why: Upilex-S is a polyimide made from biphenyl tetracarboxylic dianhydride (BPDA), a different monomer from the pyromellitic dianhydride used in Kapton. The NASA table gives the repeat unit as C22H10O4N2 with a molecular weight of 366.3320. UBE says the film has no melting point and the highest heat resistance of any plastic film it lists. The MISSE 2 flight erosion yield of 9.22e-24 cm3/atom is the largest of the polyimides NASA lists, so this is a film for ground or covered use. recipe: line: Repeat unit C22H10O4N2 from BPDA-based polycondensation (formula and molecular weight from NASA Table IV). The synthesis route and the monomer ratio were not read in this run. parts: - name: Carbon symbol: C atoms: 22 atomic_weight: 12.011 role: Backbone of the aromatic imide rings and the biphenyl units. - name: Hydrogen symbol: H atoms: 10 atomic_weight: 1.008 role: Ring hydrogens on the aromatic units. - name: Oxygen symbol: O atoms: 4 atomic_weight: 15.999 role: Carbonyl oxygens in the imide rings. - name: Nitrogen symbol: 'N' atoms: 2 atomic_weight: 14.007 role: Imide nitrogen linking the carbonyl pairs. supply: Only one manufacturer, UBE Corporation, is named in the fetched datasheet. No supply shares were read in this run. compare: In the NASA MISSE 2 table, Upilex-S eroded at 9.22e-24 cm3/atom against 3.00e-24 for Kapton H and 2.81e-24 for Kapton HN. For exposed LEO use, Upilex-S should not be chosen over Kapton HN on this evidence. No metal or composite is compared in the fetched sources. compare_rows: - label: Atomic oxygen erosion yield benchmark: atomic_oxygen_erosion_yield - label: Density benchmark: density - label: Thermal linear expansion coefficient benchmark: cte handling: - Keep the film covered in orbit. When heating above 300 degC, ventilate so DMAC and carbon monoxide stay below the UBE limits of 10 ppm and 100 ppm. Check the supplier safety data sheet before use. can_do: - label: Strength line: Insulate and carry fine circuits at temperatures from -269 degC to 300 degC, keep its size when heated (thermal linear expansion of 12 ppm/degC from 50 to 200 degC), and serve as a low-outgassing carrier film. It cannot protect itself from atomic oxygen in low Earth orbit. good_for: - Thin, flexible, electrically insulating layers that must keep their size over a wide temperature range, with a low coefficient of thermal expansion and low outgassing. watch_out: - Atomic oxygen in LEO erodes Upilex-S faster than Kapton, so bare film does not last. The 9.22e-24 value is one flight, and the NASA predicted-vs-measured table prints a conflicting figure. verdict: Upilex-S is a heat-stable polyimide insulator with a strong datasheet and a fast MISSE 2 erosion record. It is useful on the ground and under cover, and it is a poor choice for bare LEO exposure.