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Materials/Polymers/Engineering polymers

Polyimides

polyimides

5 materials across 1 types

About polyimides

Polyimides (Kapton, Upilex, PMR-15, CP1): temperature range, radiation tolerance and electrical data with sources.

Polyimides are among the most heat-resistant polymers and are used as flexible circuit film, wire insulation and spacecraft thermal blankets. Film, resin and composite forms behave differently, so each value names its form.

At a glance

  • Highest density: Upilex-S polyimide film (BPDA) reaches 1.47 g/cm³. Lowest: High temperature polyimide resin (PMR-15) starts at 1.29 g/cm³. (5 of 5 grades have a sourced value.)

Ranges run across the conditions each source reports (temper, heat treatment, form), measured at room temperature where the source says so.

How they compare

The same measurements for every material in the collection. A range means the grade has values under several conditions; "at least" means the source gives a specified minimum. "no data" means no sourced value yet. For ranked tables, open a benchmark.

Polyimides: how the grades compare
MaterialDensityTensile strengthYoung's modulusGlass transitionHeat deflection temperatureMaximum service temperature
Colorless polyimide CP1 filmflexible, optically clear polyimide film for thin-film space structures 1.42 g/cm³no datano datano datano datano data
Kapton H polyimide filmflexible insulating film, the original general-purpose grade 1.43 g/cm³no datano datano datano data400 °C
Kapton HN polyimide filmflexible insulating film 1.42 to 1.43 g/cm³no datano datano datano data400 °C
High temperature polyimide resin (PMR-15)high-temperature structural matrix resin for composites 1.29 to 1.32 g/cm³no datano data332 to 362 °Cno data316 °C
Upilex-S polyimide film (BPDA)flexible insulating film 1.39 to 1.47 g/cm³520 MPa9.1 GPano datano datano data

What these materials are made of

Composition by weight, as printed in the sources for each grade (the first constituents listed).

Composition of each grade
MaterialMain constituents
Upilex-S polyimide film (BPDA)C 72.1% · H 2.8% · O 17.5% · N 7.6%

Where they are used

Uses
UseGrades
Solar sail made of 2 micrometre CP1 film with vapour-deposited aluminumColorless polyimide CP1 film
Thin-film sunshade for a deployable space telescopeColorless polyimide CP1 film
Multilayer insulation blankets on a spacecraftKapton H polyimide film
Flexible printed circuits and flexible electronicsKapton H polyimide film
Aluminized Kapton multilayer insulation (MLI) blanketsKapton HN polyimide film
Double-aluminized Kapton sunshield sheetsKapton HN polyimide film
General-purpose film for electrical insulation and electronic partsKapton HN polyimide film
QCSEE inner cowl for an experimental turbofan engineHigh temperature polyimide resin (PMR-15)
Oil tank bracket and augmentor duct for F100 enginesHigh temperature polyimide resin (PMR-15)
Shuttle orbiter aft body flapHigh temperature polyimide resin (PMR-15)
Flexible printed circuit and TAB-tape substratesUpilex-S polyimide film (BPDA)
Carrier base and release film for high-temperature processingUpilex-S polyimide film (BPDA)
Electrical insulation in high-temperature circuitsUpilex-S polyimide film (BPDA)

When each grade fits

Best use and weak spots of each grade
MaterialBest forWeakest at
Colorless polyimide CP1 filmThin, clear, flexible film for solar sails and sunshades where the film stays uncoated in orbit only for short timesOptical darkening under UV and particle radiation (solar absorptance rose more than 0.3 in simulation), and atomic-oxygen erosion of exposed film
Kapton H polyimide filmA thin, flexible polyimide film for insulation and multilayer blankets where the film is covered or coated against atomic oxygenAtomic-oxygen erosion in low Earth orbit. The MISSE 2 flight value is 3.00e-24 cm3/atom, so bare outer film is eaten away.
Kapton HN polyimide filmA thin, flexible, electrically insulating film that works from cryogenic to about 400 degC and passes the usual outgassing screenAtomic-oxygen erosion in low Earth orbit (the outer film is eaten away unless it is covered or coated), and slow darkening under space radiation
High temperature polyimide resin (PMR-15)Structural composite parts that must hold strength at about 290 to 316 degC, such as engine ducts, cowls and fan bladesAtomic-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
Upilex-S polyimide film (BPDA)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 resistanceAtomic-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