High temperature polyimide resin (PMR-15) PI (PMR-15)
C95H57O14N6 (repeat unit as tabulated in the MISSE 2 report)
PMR-15 is NASA's polymerization of monomer reactants polyimide, a thermoset resin made by curing a mix of three monomers (MDA, BTDE and NE) into a crosslinked polyimide.
Evidence level
5 of 5
Flown or field-proven
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Recipe, share of the weight
- MDA not statedMDA (4,4'-methylenedianiline)
- BTDE not statedBTDE (dialkyl ester of benzophenone tetracarboxylic acid)
- NE not statedNE (monoalkyl ester of 5-norbornene-2,3-dicarboxylic acid)
Best for
Structural composite parts that must hold strength at about 290 to 316 degC, such as engine ducts, cowls and fan blades
Weakest at
Atomic-oxygen erosion in low Earth orbit (the MISSE 2 sample eroded through), and weight loss from thermo-oxidation at 316 degC; the MDA monomer is a carcinogen concern during manufacture
Risk at a glance
- People Low. The cured resin is not classified here; the MDA monomer is…
- If it fails High. Erosion by atomic oxygen
- Corrosion Severe. Atomic oxygen erodes PMR-15 at more than 3.02e-24 cm3 per atom, so exposed resin wears away.
Quick facts: PI (PMR-15)
| Property | Value | Basis |
|---|---|---|
| Density | 1.29 to 1.32 g/cm³ | 2 sourced values across conditions |
| Maximum service temperature | 316 °C | 1 sourced value |
What is the density of High temperature polyimide resin (PMR-15)?
High temperature polyimide resin (PMR-15) has a density of 1.29 to 1.32 g/cm³. The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the maximum service temperature of High temperature polyimide resin (PMR-15)?
High temperature polyimide resin (PMR-15) has a maximum service temperature of 316 °C. The source and test conditions are listed in the properties table on this page.
What is High temperature polyimide resin (PMR-15) used for?
Uses recorded in the sources include QCSEE inner cowl for an experimental turbofan engine; Oil tank bracket and augmentor duct for F100 engines; Shuttle orbiter aft body flap.
Why it exists
PMR-15 is the workhorse of high-temperature polyimide composites. It cures into a crosslinked resin that keeps useful flexural strength at 316 degC, which is why NASA and its partners used it for engine and airframe parts in the reports collected here.
Where it's used
Use
NASA's QCSEE experimental turbofan inner cowl, a PMR-15 composite about 90 cm across, was in ground-engine tests in 1979.
Use
The report lists PMR-15 parts for the F100 engine, including an oil tank bracket and an augmentor duct.
Use
A shuttle orbiter aft body flap, about 2 m wide by 6.5 m long, was in development as a PMR-15 structure.
Recipe
C95H57O14N6 (repeat unit as tabulated in the MISSE 2 report); PMR-15 is cured from MDA, BTDE and NE monomers
PMR-15 is made by mixing three monomers in methanol, then curing them into a crosslinked polyimide. NASA's stoichiometry is 2 NE to 3.087 MDA to 2.087 BTDE, for a formulated molecular weight of 1500 g/mole. The NE endcap limits chain growth so the melt flows and volatiles can escape.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| MDA (4,4'-methylenedianiline) MDA | not stated | The diamine. It reacts with the anhydride ester to build the polyimide chain. Molar mass 198.269 g/mol (Wikipedia infobox). |
| BTDE (dialkyl ester of benzophenone tetracarboxylic acid) BTDE | not stated | The dianhydride component, supplied as the dialkyl ester in solution. It forms the imide rings on cure. |
| NE (monoalkyl ester of 5-norbornene-2,3-dicarboxylic acid) NE | not stated | The endcap. It limits the chain length so the oligomer stays low in melt viscosity, then crosslinks at high temperature. |
Weight shares are as printed in the sources.
What it can do
Strength
Hold a flexural strength of 896 MPa at 316 degC in a graphite composite, normalised to 60 vol% fiber.
Strength
Keep a glass transition of 332 degC in the neat resin and 341 degC in the composite.
Strength
Be used for structures up to 316 degC, with a stepwise postcure.
How it compares
PMR-15 is a high-temperature thermoset, so its strength is kept at 316 degC by the crosslinked network, and its density (1.287 g/cm3) is typical of aromatic polyimides. Its erosion in low Earth orbit is high, so it needs a protective cover there. The table compares it with its two nearest benchmarks in the collection.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Other materials are shown beside it; each was measured under its own conditions, so open its page before comparing closely. Compare every grade in the family.
| Measurement | PI (PMR-15) | PI (CP1) | PI (Kapton H) | PI (Kapton HN) | PI (Upilex-S) |
|---|---|---|---|---|---|
| Physical and electrical | |||||
| Density of neat resin (postcured) | 1.287 g/cm³1 | 1.419 g/cm³ | 1.427 g/cm³ | 1.42 g/cm³ | 1.387 g/cm³ |
| Density of PMR-15 (MISSE 2 reference) | 1.323 g/cm³2 | 1.419 g/cm³ | 1.427 g/cm³ | 1.42 g/cm³ | 1.387 g/cm³ |
| Temperature behavior | |||||
| Glass transition temperature, neat resin | 332 °C3 | no data | no data | no data | no data |
| Glass transition temperature, dry film by dynamic mechanical analysis | 362 °C4 | no data | no data | no data | no data |
| Glass transition temperature, resin with absorbed moistureValue stated in NASA technical memorandum text | 349 °C5 | no data | no data | no data | no data |
| Glass transition temperature, PMR-15 graphite composite | 341 °C6 | no data | no data | no data | no data |
| Other measurements | |||||
| Highest structural use temperature stated by NASA | 316 °C7 | no data | 400 °C | 400 °C | no data |
| Atomic oxygen erosion yield, MISSE 2 flight | > 3.02×10^-24 cm³/atom8 | 1.91×10^-24 cm³/atom | 3×10^-24 cm³/atom | 2.81×10^-24 cm³/atom | 9.22×10^-24 cm³/atom |
| Atomic oxygen erosion yield, predicted by the NASA tool | 2.27×10^-24 cm³/atom9 | 1.91×10^-24 cm³/atom | 3×10^-24 cm³/atom | 2.81×10^-24 cm³/atom | 9.22×10^-24 cm³/atom |
| Weight loss of neat resin in air at 316 degC | 16.3 %10 | no data | no data | no data | no data |
| Weight loss of PMR-15 graphite composite in air at 316 degC | 7.4 %11 | no data | no data | no data | no data |
| Flexural strength of PMR-15 graphite composite at 316 degC | 896 MPa12 | no data | no data | no data | no data |
| Flexural modulus of PMR-15 graphite composite at 316 degC | 112 GPa13 | no data | no data | no data | no data |
| Interlaminar shear strength of PMR-15 graphite composite at 316 degC | 50.7 MPa14 | no data | no data | no data | no data |
Why choose it, and why not
Good for
- Structural composites at 290 to 316 degC, such as engine ducts and cowls.
- Parts that must hold flexural strength at 316 degC for many hours in air (7.4 percent composite weight loss after 1512 hr).
Watch out for
- MDA is a suspected carcinogen and mutagen, which raises manufacturing cost and handling needs.
- Atomic oxygen erodes PMR-15 in orbit; the MISSE 2 sample eroded through.
- Neat resin loses 16.3 percent of its weight in 151 hours at 316 degC in air.
PMR-15 is the proven high-temperature composite resin in this collection. It keeps strength at 316 degC, but it needs careful handling in making and protection from atomic oxygen in orbit.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Density of neat resin (postcured) | Value printed in NASA report table of neat PMR polyimide resins | product PMR-15 molding powder, neat resin diskspostcure 16 hr in air at 204 °C plus 24 hr in air at 316 °Cstoichiometry 2NE / 3.087MDA / 2.087BTDE | — |
| 2 | Density of PMR-15 (MISSE 2 reference) | Density from the MISSE 2 report, table column headed ref. 12, rho | product PMR-15 sample from the MISSE 2 PEACE polymers traytemperature not stated in the table | The neat-resin report gives 1.287 g/cm3, so the two sources differ by about 3 percent. |
| 3 | Glass transition temperature, neat resin | Value printed in NASA report table of neat PMR polyimide resins | product PMR-15 neat resin, postcuredpostcure 16 hr in air at 204 °C plus 24 hr in air at 316 °Ctest value printed in the Tg column of the neat-resin table (the header is partly garbled in the scan and is read as Tg in °C) | — |
| 4 | Glass transition temperature, dry film by dynamic mechanical analysis | Value stated in NASA technical memorandum text; the authors report the Tg from this method is within 5 degC of thermo-mechanical analysis | product PMR-15 addition-cured resin, dried in an oven at 120 °C for 150 hrmethod note storage modulus with tan delta, scanned at 10 °C/min | — |
| 5 | Glass transition temperature, resin with absorbed moisture | — | product PMR-15 addition-cured resin, sample held in moist conditions (above refluxing water)method note storage modulus with tan delta, scanned at 10 °C/min | The authors say the drop may be larger than shown because some moisture is lost during the ramp to Tg. |
| 6 | Glass transition temperature, PMR-15 graphite composite | Value printed in NASA report table of PMR polyimide/Celion 6000 composites | product PMR-15 unidirectional Celion 6000 graphite fibre compositepostcure 24 hr in air at 316 °Cfiber content 60.2 (as printed in the Fiber column; the footnote says normalized to 60 vol% fiber) | — |
| 7 | Highest structural use temperature stated by NASA | Statement in NASA report text; a design statement, not a tested rating | product PMR-15 composite structures, postcuredbasis the report says the resin allows structures to be designed for use up to 316 °C | — |
| 8 | Atomic oxygen erosion yield, MISSE 2 flight | Mass-loss erosion yield from the MISSE 2 flight sample, as printed with a greater-than sign | experiment MISSE 2 PEACE polymers, PEC 2 tray 1, exterior of the ISS Quest airlockexposure 3.95 yr in low Earth orbit, 16 August 2001 to 30 July 2005fluence 8.43e21 atoms/cm2 | The report prints a greater-than sign, so 3.02e-24 is a lower bound (the sample eroded through). |
| 9 | Atomic oxygen erosion yield, predicted by the NASA tool | Predicted value from the NASA predictive tool, printed as the predicted column of the comparison table | method predictive tool based on repeat-unit chemistry, density and bond counts, fitted to the MISSE 2 data | The predicted value is 2.27e-24 against a measured lower bound of more than 3.02e-24, so the tool underpredicts this resin. |
| 10 | Weight loss of neat resin in air at 316 degC | Value printed in NASA report table of neat PMR polyimide resins, footnote b | product PMR-15 neat resin, postcuredexposure 151 hr in air at 316 °C | This is a non-canonical benchmark name (thermo_oxidative_weight_loss). It has no entry in the canonical list. |
| 11 | Weight loss of PMR-15 graphite composite in air at 316 degC | Value printed in NASA report table of PMR polyimide/Celion 6000 composites, footnote c | product PMR-15 unidirectional Celion 6000 graphite fibre compositeexposure 1512 hr in air at 316 °C | Non-canonical benchmark name (thermo_oxidative_weight_loss). |
| 12 | Flexural strength of PMR-15 graphite composite at 316 degC | Value printed in NASA report table of PMR polyimide/Celion 6000 composites (footnote b, normalized to 60 vol% fiber) | product PMR-15 unidirectional Celion 6000 graphite fibre composite, normalized to 60 vol% fibertemperature 316 °C (header reads as 316 °C; the scan is partly garbled, read as 316)postcure 24 hr in air at 316 °C | — |
| 13 | Flexural modulus of PMR-15 graphite composite at 316 degC | Value printed in NASA report table of PMR polyimide/Celion 6000 composites (footnote b, normalized to 60 vol% fiber) | product PMR-15 unidirectional Celion 6000 graphite fibre composite, normalized to 60 vol% fibertemperature 316 °C (header reads as 316 °C; the scan is partly garbled, read as 316)postcure 24 hr in air at 316 °C | — |
| 14 | Interlaminar shear strength of PMR-15 graphite composite at 316 degC | Value printed in NASA report table of PMR polyimide/Celion 6000 composites | product PMR-15 unidirectional Celion 6000 graphite fibre compositetemperature 316 °C (header reads as 316 °C; the scan is partly garbled, read as 316)postcure 24 hr in air at 316 °C | — |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Atomic oxygen in low Earth orbit | severe | Atomic oxygen erodes PMR-15 at more than 3.02e-24 cm3 per atom, so exposed resin wears away.1 |
| Air at 316 degC (thermo-oxidative ageing) | moderate | At 316 degC in air the neat resin lost 16.3 percent of its weight after 151 hours.2 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Atomic oxygen in low Earth orbit | On MISSE 2 (3.95 years on the ISS, fluence 8.43e21 atoms/cm2), the PMR-15 sample eroded through, so the printed erosion yield of more than 3.02e-24 cm3/atom is a lower bound. Its predicted value is 2.27e-24 cm3/atom, lower than the measurement. | flight MISSE 2, PEC 2 tray 1, 3.95 yr, fluence 8.43e21 atoms/cm2 |
| 2 | Air at 316 degC (thermo-oxidative ageing) | The neat PMR-15 resin lost 16.3 percent weight after 151 hours in air at 316 degC. A PMR-15 graphite composite lost 7.4 percent after 1512 hours in air at 316 degC. The authors compared the composite with its own PMR-NV variants, which are not PMR-15. | neat resin 151 hr in air at 316 °Ccomposite 1512 hr in air at 316 °C, Celion 6000 graphite fibre |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
The main hazard is in making the resin, not in the finished part. MDA is a suspected carcinogen and mutagen.
- MDA monomer
- MDA carries H350 (may cause cancer), H341 (suspected of causing genetic defects) and H370 (organ damage), signal word Danger, according to the Wikipedia infobox. NASA Glenn calls it a mutagen and suspect carcinogen.
- Cost
- NASA Glenn says the monomer is inexpensive, but the health and safety handling adds to the manufacturing cost of PMR-15.
If it fails
These results come from flight exposure and laboratory ageing, not from failures of flight hardware.
- Atomic oxygen
- On MISSE 2 the sample eroded through, so the erosion yield is more than 3.02e-24 cm3/atom. Exposed resin does not last in low Earth orbit.
- Heat in air
- Neat resin lost 16.3 percent of its weight in 151 hours at 316 degC in air.
- Sudden heat
- Cured parts placed suddenly into 316 degC blistered, because residual endcap volatiles escape.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Erosion by atomic oxygenhigh severity | Exposed PMR-15 in low Earth orbit (MISSE 2, 8.43e21 atoms/cm2 over 3.95 years)The sample eroded through, so a thin unprotected resin skin would not last. |
| Blistering from residual endcap and volatilesmoderate severity | Placing a cured neat resin suddenly into a 316 degC oven without a stepwise postcureWarping and blistering occurred in several instances; the report says residual unreacted norbornene endcaps can release volatiles at 316 degC. |
| Loss of resin mass at the top use temperaturemoderate severity | Long exposure to air at 316 degCThe neat resin loses 16.3 percent of its weight in 151 hours, and the composite loses 7.4 percent in 1512 hours. |
Side effects on surrounding parts
| Affects | Effect |
|---|---|
| Nearby optics and infrared instruments | Erosion products from the polymer are volatile and add to the gas around the spacecraft, which can matter for nearby optics. |
Handling and storage
- Use the monomers in a controlled workplace. MDA is a suspected carcinogen, and the report says health and safety issues raise manufacturing costs.
- Postcure in steps. Final cure is at 288 to 316 degC, and sudden exposure of a cured resin to 316 degC causes blisters.
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
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spore: profile
id: pi-pmr-15
spore_version: 0.2
family: polyimides
name: High temperature polyimide resin (PMR-15)
abbreviation: PI (PMR-15)
role: high-temperature structural matrix resin for composites
category: polymers
type: polyimides
summary: |
PMR-15 is NASA's polymerization of monomer reactants polyimide, a thermoset resin made by curing a mix of three monomers (MDA, BTDE and NE) into a crosslinked polyimide. The neat resin has a density of 1.287 g/cm3 and a glass transition temperature of 332 degC, and NASA's own work gives 316 degC as the highest temperature for structures. In low Earth orbit the MISSE 2 flight on the ISS eroded it at more than 3.02e-24 cm3/atom, and the sample was eroded through, so the true yield is higher. The monomer MDA is a suspect carcinogen, which is why the resin is costly to make.
best_for: Structural composite parts that must hold strength at about 290 to 316 degC, such as engine ducts, cowls and fan blades
weakest_at: Atomic-oxygen erosion in low Earth orbit (the MISSE 2 sample eroded through), and weight loss from thermo-oxidation at 316 degC; the MDA monomer is a carcinogen concern during manufacture
identity:
formula: C95H57O14N6 (repeat unit as tabulated in the MISSE 2 report); PMR-15 is cured from MDA, BTDE and NE monomers
source: banks2008
where: Table IV (PI (PMR-15) formula C95H57O14N6, molecular weight 1506.5271 g/mole); monomer composition from nasa1980 and johnston2007
tags:
environments:
- low-earth-orbit
stresses:
- atomic-oxygen
applications:
- structures
- propulsion-and-tanks
properties:
- benchmark: density
label: Density of neat resin (postcured)
value: 1.287
unit: g/cm3
scope: material
conditions:
product: PMR-15 molding powder, neat resin disks
postcure: 16 hr in air at 204 degC plus 24 hr in air at 316 degC
stoichiometry: 2NE / 3.087MDA / 2.087BTDE
method: Value printed in NASA report table of neat PMR polyimide resins
status: ground
source: serafini1983
where: Table II (PMR-15 row, density column)
- benchmark: density
label: Density of PMR-15 (MISSE 2 reference)
value: 1.3232
unit: g/cm3
scope: material
conditions:
product: PMR-15 sample from the MISSE 2 PEACE polymers tray
temperature: not stated in the table
method: Density from the MISSE 2 report, table column headed ref. 12, rho
status: ground
note: The neat-resin report gives 1.287 g/cm3, so the two sources differ by about 3 percent.
source: banks2008
where: Table II (PI (PMR-15) row)
- benchmark: glass_transition_temperature
label: Glass transition temperature, neat resin
value: 332
unit: degC
scope: material
conditions:
product: PMR-15 neat resin, postcured
postcure: 16 hr in air at 204 degC plus 24 hr in air at 316 degC
test: value printed in the Tg column of the neat-resin table (the header is partly garbled in the scan and is read as Tg in degC)
method: Value printed in NASA report table of neat PMR polyimide resins
status: ground
source: serafini1983
where: Table II (PMR-15 row, Tg column)
- benchmark: glass_transition_temperature
label: Glass transition temperature, dry film by dynamic mechanical analysis
value: 362
unit: degC
scope: material
conditions:
product: PMR-15 addition-cured resin, dried in an oven at 120 degC for 150 hr
method_note: storage modulus with tan delta, scanned at 10 degC/min
method: Value stated in NASA technical memorandum text; the authors report the Tg from this method is within 5 degC of thermo-mechanical analysis
status: ground
source: nasa1991
where: Viscoelastic properties section, Figure 1 text
- benchmark: glass_transition_temperature
label: Glass transition temperature, resin with absorbed moisture
value: 349
unit: degC
scope: material
conditions:
product: PMR-15 addition-cured resin, sample held in moist conditions (above refluxing water)
method_note: storage modulus with tan delta, scanned at 10 degC/min
method: Value stated in NASA technical memorandum text
status: ground
note: The authors say the drop may be larger than shown because some moisture is lost during the ramp to Tg.
source: nasa1991
where: Viscoelastic properties section, Figure 1 text
- benchmark: glass_transition_temperature
label: Glass transition temperature, PMR-15 graphite composite
value: 341
unit: degC
scope: material
conditions:
product: PMR-15 unidirectional Celion 6000 graphite fibre composite
postcure: 24 hr in air at 316 degC
fiber_content: 60.2 (as printed in the Fiber column; the footnote says normalized to 60 vol% fiber)
method: Value printed in NASA report table of PMR polyimide/Celion 6000 composites
status: ground
source: serafini1983
where: Table IV (PMR-15 row, Tg column)
- benchmark: max_service_temp
label: Highest structural use temperature stated by NASA
value: 316
unit: degC
scope: material
conditions:
product: PMR-15 composite structures, postcured
basis: the report says the resin allows structures to be designed for use up to 316 degC
method: Statement in NASA report text; a design statement, not a tested rating
status: ground
source: serafini1983
where: Introduction (page 1 text)
- benchmark: atomic_oxygen_erosion_yield
label: Atomic oxygen erosion yield, MISSE 2 flight
value: 3.02e-24
bound: lower
unit: cm3/atom
scope: material
conditions:
experiment: MISSE 2 PEACE polymers, PEC 2 tray 1, exterior of the ISS Quest airlock
exposure: 3.95 yr in low Earth orbit, 16 August 2001 to 30 July 2005
fluence: 8.43e21 atoms/cm2
method: Mass-loss erosion yield from the MISSE 2 flight sample, as printed with a greater-than sign
status: flight
note: The report prints a greater-than sign, so 3.02e-24 is a lower bound (the sample eroded through).
source: banks2008
where: Table I (PI (PMR-15) row); Section 2.1 for exposure
- benchmark: atomic_oxygen_erosion_yield
label: Atomic oxygen erosion yield, predicted by the NASA tool
value: 2.27e-24
unit: cm3/atom
scope: material
conditions:
method: predictive tool based on repeat-unit chemistry, density and bond counts, fitted to the MISSE 2 data
method: Predicted value from the NASA predictive tool, printed as the predicted column of the comparison table
status: calculated
note: The predicted value is 2.27e-24 against a measured lower bound of more than 3.02e-24, so the tool underpredicts this resin.
source: banks2008
where: Table VII (PMR-15 row, predicted column)
- benchmark: thermo_oxidative_weight_loss
label: Weight loss of neat resin in air at 316 degC
value: 16.3
unit: '%'
scope: material
conditions:
product: PMR-15 neat resin, postcured
exposure: 151 hr in air at 316 degC
method: Value printed in NASA report table of neat PMR polyimide resins, footnote b
status: ground
note: This is a non-canonical benchmark name (thermo_oxidative_weight_loss). It has no entry in the canonical list.
source: serafini1983
where: Table II (PMR-15 row, weight loss column; footnote b)
- benchmark: thermo_oxidative_weight_loss
label: Weight loss of PMR-15 graphite composite in air at 316 degC
value: 7.4
unit: '%'
scope: material
conditions:
product: PMR-15 unidirectional Celion 6000 graphite fibre composite
exposure: 1512 hr in air at 316 degC
method: Value printed in NASA report table of PMR polyimide/Celion 6000 composites, footnote c
status: ground
note: Non-canonical benchmark name (thermo_oxidative_weight_loss).
source: serafini1983
where: Table IV (PMR-15 row, weight loss column; footnote c)
- benchmark: flexural_strength
label: Flexural strength of PMR-15 graphite composite at 316 degC
value: 896
unit: MPa
scope: material
conditions:
product: PMR-15 unidirectional Celion 6000 graphite fibre composite, normalized to 60 vol% fiber
temperature: 316 degC (header reads as 316 degC; the scan is partly garbled, read as 316)
postcure: 24 hr in air at 316 degC
method: Value printed in NASA report table of PMR polyimide/Celion 6000 composites (footnote b, normalized to 60 vol% fiber)
status: ground
source: serafini1983
where: Table IV (PMR-15 row, flexural strength column)
- benchmark: flexural_modulus
label: Flexural modulus of PMR-15 graphite composite at 316 degC
value: 112
unit: GPa
scope: material
conditions:
product: PMR-15 unidirectional Celion 6000 graphite fibre composite, normalized to 60 vol% fiber
temperature: 316 degC (header reads as 316 degC; the scan is partly garbled, read as 316)
postcure: 24 hr in air at 316 degC
method: Value printed in NASA report table of PMR polyimide/Celion 6000 composites (footnote b, normalized to 60 vol% fiber)
status: ground
source: serafini1983
where: Table IV (PMR-15 row, flexural modulus column)
- benchmark: interlaminar_shear_strength
label: Interlaminar shear strength of PMR-15 graphite composite at 316 degC
value: 50.7
unit: MPa
scope: material
conditions:
product: PMR-15 unidirectional Celion 6000 graphite fibre composite
temperature: 316 degC (header reads as 316 degC; the scan is partly garbled, read as 316)
postcure: 24 hr in air at 316 degC
method: Value printed in NASA report table of PMR polyimide/Celion 6000 composites
status: ground
source: serafini1983
where: Table IV (PMR-15 row, interlaminar shear strength column)
corrosion:
- environment: Atomic oxygen in low Earth orbit
headline: Atomic oxygen erodes PMR-15 at more than 3.02e-24 cm3 per atom, so exposed resin wears away.
effect: On MISSE 2 (3.95 years on the ISS, fluence 8.43e21 atoms/cm2), the PMR-15 sample eroded through, so the printed erosion yield of more than 3.02e-24 cm3/atom is a lower bound. Its predicted value is 2.27e-24 cm3/atom, lower than the measurement.
rating: severe
conditions:
flight: MISSE 2, PEC 2 tray 1, 3.95 yr, fluence 8.43e21 atoms/cm2
source: banks2008
where: Table I; Table VII; Section 2.1
- environment: Air at 316 degC (thermo-oxidative ageing)
headline: At 316 degC in air the neat resin lost 16.3 percent of its weight after 151 hours.
effect: The neat PMR-15 resin lost 16.3 percent weight after 151 hours in air at 316 degC. A PMR-15 graphite composite lost 7.4 percent after 1512 hours in air at 316 degC. The authors compared the composite with its own PMR-NV variants, which are not PMR-15.
rating: moderate
conditions:
neat_resin: 151 hr in air at 316 degC
composite: 1512 hr in air at 316 degC, Celion 6000 graphite fibre
source: serafini1983
where: Table II (footnote b); Table IV (footnote c)
risks:
hazards:
- text: MDA, the aromatic diamine used to make PMR-15, is listed under GHS with H350 (may cause cancer), H341 (suspected of causing genetic defects), H317 (may cause an allergic skin reaction), H370 (causes damage to organs), H373 (may cause damage to organs after repeated exposure) and H411 (toxic to aquatic life with long lasting effects), signal word Danger. The cured resin is not classified by this source.
ghs:
- H317
- H341
- H350
- H370
- H373
- H411
source: wiki-mda
where: Infobox (hazard statements and signal word)
- text: NASA Glenn describes MDA as a mutagen and suspect carcinogen, and says that the health and safety issues it raises add to the manufacturing cost of PMR-15 even though the raw material itself is inexpensive.
ghs: []
source: johnston2007
where: Abstract (page 1)
failure_risks:
- mode: Erosion by atomic oxygen
trigger: Exposed PMR-15 in low Earth orbit (MISSE 2, 8.43e21 atoms/cm2 over 3.95 years)
consequence: The sample eroded through, so a thin unprotected resin skin would not last.
severity: high
source: banks2008
where: Table I; Section 2.1
- mode: Blistering from residual endcap and volatiles
trigger: Placing a cured neat resin suddenly into a 316 degC oven without a stepwise postcure
consequence: Warping and blistering occurred in several instances; the report says residual unreacted norbornene endcaps can release volatiles at 316 degC.
severity: moderate
source: serafini1983
where: Text on the postcure schedule (page 3)
- mode: Loss of resin mass at the top use temperature
trigger: Long exposure to air at 316 degC
consequence: The neat resin loses 16.3 percent of its weight in 151 hours, and the composite loses 7.4 percent in 1512 hours.
severity: moderate
source: serafini1983
where: Table II; Table IV
side_effects:
- text: Erosion products from the polymer are volatile and add to the gas around the spacecraft, which can matter for nearby optics.
affects: Nearby optics and infrared instruments
source: banks2008
where: Section 2.1 context (MISSE 2 erosion data)
handling:
- text: Use the monomers in a controlled workplace. MDA is a suspected carcinogen, and the report says health and safety issues raise manufacturing costs.
source: johnston2007
where: Abstract (page 1)
- text: Postcure in steps. Final cure is at 288 to 316 degC, and sudden exposure of a cured resin to 316 degC causes blisters.
source: serafini1983
where: Experimental and text sections on cure and postcure
uses:
- application: propulsion-and-tanks
device: QCSEE inner cowl for an experimental turbofan engine
example: The QCSEE (Quiet Clean Short Haul Experimental Engine) inner cowl, a part of an experimental GE turbofan with a maximum diameter of about 90 cm, was made from PMR-15 composite and was undergoing ground-engine tests when the report was written.
source: nasa1979
where: Section 1, Applications (page 1)
- application: propulsion-and-tanks
device: Oil tank bracket and augmentor duct for F100 engines
example: PMR-15 parts listed in the report include an oil tank bracket for the F100 engine (chopped graphite molding compound by Pratt and Whitney/TRW) and an augmentor duct for the F100 engine (Composites Horizons, Air Force).
source: nasa1979
where: Section 1, Applications, Table III
- application: structures
device: Shuttle orbiter aft body flap
example: The report lists a shuttle orbiter aft body flap being developed by Boeing, about 2 m wide by 6.5 m long, as a PMR-15 structure.
source: nasa1979
where: Section 1, Applications (page 1)
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: NASA TM 79039, PMR-15 applications report (presented at a 1979 conference, Honolulu)
type: report
url: https://ntrs.nasa.gov/api/citations/19790003979/downloads/19790003979.pdf
year: 1979
- title: NASA technical report on PMR polyimide neat resins and Celion 6000 composites (NTRS 19830001848)
type: report
url: https://ntrs.nasa.gov/api/citations/19830001848/downloads/19830001848.pdf
year: 1983
- title: 'NASA Technical Memorandum 103768: Viscoelastic Properties of Addition-Cured Polyimide PMR-15 (NTRS 19910013064)'
type: report
url: https://ntrs.nasa.gov/api/citations/19910013064/downloads/19910013064.pdf
year: 1991
- title: Johnston and Kuczmarski, NASA Glenn, N-15 NMR study of imidization rates of diamines (NTRS 20070023557)
type: report
url: https://ntrs.nasa.gov/api/citations/20070023557/downloads/20070023557.pdf
year: 2007
- title: NASA report on PMR-15 monomers and MDA (NTRS 20020024447)
type: report
url: https://ntrs.nasa.gov/api/citations/20020024447/downloads/20020024447.pdf
year: 2002
- title: NASA report on PMR-15 composite fabrication and monomer chemistry (NTRS 19800020932)
type: report
url: https://ntrs.nasa.gov/api/citations/19800020932/downloads/19800020932.pdf
year: 1980
- title: Wikipedia, 4,4'-Methylenedianiline (infobox)
type: report
url: https://en.wikipedia.org/wiki/4,4%27-Methylenedianiline
year: 2026
gaps:
- 'Supply: no source was read for PMR-15 resin or its monomers (MDA, BTDE, NE) for producers, country shares, or critical-mineral lists, so there is no supply section.'
- Moisture uptake, hygroscopic swelling and thermal cycling for PMR-15 were not found in pages read here.
- Room-temperature mechanical properties (tensile, flexural, compressive) of neat PMR-15 were not entered; only the 316 degC composite values from Table IV were.
- Total ionizing dose and UV tolerance for PMR-15 were not found in a source read in this run.
- Current commercial prepreg suppliers and the state of AMB-21 or other MDA replacements were not checked in a fetched source; the search snippet on AMB-21 was not used.
- The MISSE 2 erosion value is a lower bound (the sample eroded through), so no measured yield is available.
- The monomer molar masses and CAS number for BTDE and NE were not read, so the recipe lists the stoichiometry only.
- Two non-canonical benchmark names were used (thermo_oxidative_weight_loss); no canonical name exists for them in spores/property-canon.yaml.
- The Table IV Tg and flexural columns in the NASA scan are partly garbled, so the test temperature was read from the header as 316 degC.
sources:
banks2008:
title: Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit
id: NASA/TM-2008-215490, NTRS 20090011780 (Banks, Backus and de Groh, December 2008)
url: https://ntrs.nasa.gov/citations/20090011780
year: 2008
kind: report
license: public domain (NASA)
serafini1983:
title: NASA report on PMR polyimide neat resins and Celion 6000 graphite composites (NTRS 19830001848)
id: NTRS 19830001848 (1983)
url: https://ntrs.nasa.gov/api/citations/19830001848/downloads/19830001848.pdf
year: 1983
kind: report
license: NASA NTRS document, linked not reproduced
note: Table II gives PMR-15 stoichiometry 2NE/3.087MDA/2.087BTDE. Table IV gives composite Tg 341, flexural strength 896 MPa, flexural modulus 112 GPa, interlaminar shear 50.7 MPa, weight loss 7.4 percent after 1512 hr at 316 degC. Text gives use up to 316 degC.
nasa1991:
title: Viscoelastic Properties of Addition-Cured Polyimide PMR-15, NASA Technical Memorandum 103768
id: NTRS 19910013064 (1991)
url: https://ntrs.nasa.gov/api/citations/19910013064/downloads/19910013064.pdf
year: 1991
kind: report
license: NASA NTRS document, linked not reproduced
note: Tg dry 362 degC and 349 degC with moisture, by dynamic mechanical analysis, within 5 degC of TMA.
johnston2007:
title: N-15 NMR spectroscopy as a method for comparing the rates of imidization of several diamines (Johnston and Kuczmarski, NASA Glenn)
id: NTRS 20070023557 (2007)
url: https://ntrs.nasa.gov/api/citations/20070023557/downloads/20070023557.pdf
year: 2007
kind: report
license: NASA NTRS document, linked not reproduced
note: PMR-15 is made from MDA, BTDE and NE monomers; oligomer molecular weight 1500 g/mole; MDA is a mutagen and suspect carcinogen.
ntrs2002:
title: NASA report on PMR-15 monomers and MDA replacement diamines (NTRS 20020024447)
id: NTRS 20020024447 (2002)
url: https://ntrs.nasa.gov/api/citations/20020024447/downloads/20020024447.pdf
year: 2002
kind: report
license: NASA NTRS document, linked not reproduced
note: States that MDA is a mutagen and suspected carcinogen used in PMR-15 polyimide.
nasa1979:
title: NASA Technical Memorandum 79039, PMR-15 applications (presented at a 1979 conference, Honolulu)
id: NTRS 19790003979 (1979)
url: https://ntrs.nasa.gov/api/citations/19790003979/downloads/19790003979.pdf
year: 1979
kind: report
license: NASA NTRS document, linked not reproduced
note: Lists QCSEE inner cowl, F100 engine oil tank bracket and augmentor duct, shuttle orbiter aft body flap, and max cure of 316 degC (600 degF).
nasa1980:
title: NASA report on PMR-15 composite fabrication, monomers and glass transition (NTRS 19800020932)
id: NTRS 19800020932 (1980)
url: https://ntrs.nasa.gov/api/citations/19800020932/downloads/19800020932.pdf
year: 1980
kind: report
license: NASA NTRS document, linked not reproduced
note: Describes the PMR-15 system as NE, BTDA-derived dimethyl ester and MDA, with formulated molecular weight 1500 (n = 2.087).
wiki-mda:
title: Wikipedia, 4,4'-Methylenedianiline (infobox)
url: https://en.wikipedia.org/wiki/4,4%27-Methylenedianiline
kind: web
license: CC BY-SA (Wikipedia)
note: CAS 101-77-9; molar mass 198.269 g/mol; hazard statements H317, H341, H350, H370, H373, H411; signal word Danger; IARC Group 2B.
license: CC-BY-4.0
updated: '2026-10-20'
review:
status: draft
method: assistant
checked_values: 14
unreachable: 0
caveats: 4
note: 'Written by an AI assistant on 2026-10-20. Values were read from text and tables of NASA NTRS PDFs downloaded in this run (MISSE 2 report, 1979, 1980, 1983, 1991 and 2002 reports, and the 2007 NMR paper) and from the Wikipedia MDA infobox. Caveats: the MISSE 2 erosion yield is a lower bound; the composite table header is partly garbled; the density differs between sources; supply is absent.'
story:
recipe:
line: PMR-15 is made by mixing three monomers in methanol, then curing them into a crosslinked polyimide. NASA's stoichiometry is 2 NE to 3.087 MDA to 2.087 BTDE, for a formulated molecular weight of 1500 g/mole. The NE endcap limits chain growth so the melt flows and volatiles can escape.
parts:
- name: MDA (4,4'-methylenedianiline)
symbol: MDA
share: 3.087 mol per formulation
role: The diamine. It reacts with the anhydride ester to build the polyimide chain. Molar mass 198.269 g/mol (Wikipedia infobox).
- name: BTDE (dialkyl ester of benzophenone tetracarboxylic acid)
symbol: BTDE
share: 2.087 mol per formulation
role: The dianhydride component, supplied as the dialkyl ester in solution. It forms the imide rings on cure.
- name: NE (monoalkyl ester of 5-norbornene-2,3-dicarboxylic acid)
symbol: NE
share: 2 mol per formulation
role: The endcap. It limits the chain length so the oligomer stays low in melt viscosity, then crosslinks at high temperature.
risk_groups:
- title: For people
level: 1
verdict: The cured resin is not classified here; the MDA monomer is…
lead: The main hazard is in making the resin, not in the finished part. MDA is a suspected carcinogen and mutagen.
points:
- label: MDA monomer
line: MDA carries H350 (may cause cancer), H341 (suspected of causing genetic defects) and H370 (organ damage), signal word Danger, according to the Wikipedia infobox. NASA Glenn calls it a mutagen and suspect carcinogen.
- label: Cost
line: NASA Glenn says the monomer is inexpensive, but the health and safety handling adds to the manufacturing cost of PMR-15.
- title: If it fails
lead: These results come from flight exposure and laboratory ageing, not from failures of flight hardware.
points:
- label: Atomic oxygen
line: On MISSE 2 the sample eroded through, so the erosion yield is more than 3.02e-24 cm3/atom. Exposed resin does not last in low Earth orbit.
- label: Heat in air
line: Neat resin lost 16.3 percent of its weight in 151 hours at 316 degC in air.
- label: Sudden heat
line: Cured parts placed suddenly into 316 degC blistered, because residual endcap volatiles escape.
why: PMR-15 is the workhorse of high-temperature polyimide composites. It cures into a crosslinked resin that keeps useful flexural strength at 316 degC, which is why NASA and its partners used it for engine and airframe parts in the reports collected here.
uses:
- where: Use
line: NASA's QCSEE experimental turbofan inner cowl, a PMR-15 composite about 90 cm across, was in ground-engine tests in 1979.
- where: Use
line: The report lists PMR-15 parts for the F100 engine, including an oil tank bracket and an augmentor duct.
- where: Use
line: A shuttle orbiter aft body flap, about 2 m wide by 6.5 m long, was in development as a PMR-15 structure.
can_do:
- label: Strength
line: Hold a flexural strength of 896 MPa at 316 degC in a graphite composite, normalised to 60 vol% fiber.
- label: Strength
line: Keep a glass transition of 332 degC in the neat resin and 341 degC in the composite.
- label: Strength
line: Be used for structures up to 316 degC, with a stepwise postcure.
compare: PMR-15 is a high-temperature thermoset, so its strength is kept at 316 degC by the crosslinked network, and its density (1.287 g/cm3) is typical of aromatic polyimides. Its erosion in low Earth orbit is high, so it needs a protective cover there. The table compares it with its two nearest benchmarks in the collection.
compare_rows:
- label: Density
benchmark: density
- label: Glass transition
benchmark: glass_transition_temperature
- label: Atomic oxygen erosion
benchmark: atomic_oxygen_erosion_yield
handling:
- 'Treat MDA as a carcinogen during resin making: control the workplace and limit exposure.'
- Postcure in steps, up to 316 degC, so volatiles escape before the final heat.
- Protect exposed resin in low Earth orbit, because it erodes.
good_for:
- Structural composites at 290 to 316 degC, such as engine ducts and cowls.
- Parts that must hold flexural strength at 316 degC for many hours in air (7.4 percent composite weight loss after 1512 hr).
watch_out:
- MDA is a suspected carcinogen and mutagen, which raises manufacturing cost and handling needs.
- Atomic oxygen erodes PMR-15 in orbit; the MISSE 2 sample eroded through.
- Neat resin loses 16.3 percent of its weight in 151 hours at 316 degC in air.
verdict: PMR-15 is the proven high-temperature composite resin in this collection. It keeps strength at 316 degC, but it needs careful handling in making and protection from atomic oxygen in orbit.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
| # | Source | Type | Year | Used for |
|---|---|---|---|---|
| Atomic Oxygen Erosion Yield Predictive Tool for Spacecraft Polymers in Low Earth Orbit | report | 2008 | 7 values | |
| NASA report on PMR polyimide neat resins and Celion 6000 graphite composites (NTRS 19830001848) | report | 1983 | 13 values | |
| Viscoelastic Properties of Addition-Cured Polyimide PMR-15, NASA Technical Memorandum 103768 | report | 1991 | 2 values | |
| N-15 NMR spectroscopy as a method for comparing the rates of imidization of several diamines (Johnston and Kuczmarski, NASA Glenn) | report | 2007 | 2 values | |
| NASA report on PMR-15 monomers and MDA replacement diamines (NTRS 20020024447) | report | 2002 | 0 values | |
| NASA Technical Memorandum 79039, PMR-15 applications (presented at a 1979 conference, Honolulu) | report | 1979 | 3 values | |
| NASA report on PMR-15 composite fabrication, monomers and glass transition (NTRS 19800020932) | report | 1980 | 0 values | |
| Wikipedia, 4,4'-Methylenedianiline (infobox) | web | 1 value |