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Structure of poly-oxydiphenylene-pyromellitimide Poly-oxydiphenylene-pyromellitimide.png
Structure of poly-oxydiphenylene-pyromellitimide
Kapton insulating pads for mounting electronic parts on a heat sink Kaptonpads.jpg
Kapton insulating pads for mounting electronic parts on a heat sink
Aluminized Kapton thermal cover was used on the Ultra Heavy Cosmic Ray Experiment EL-1994-00018.jpeg
Aluminized Kapton thermal cover was used on the Ultra Heavy Cosmic Ray Experiment
Kapton tapes, three rolls of different widths Kapton tapes, three rolls of different widths.jpg
Kapton tapes, three rolls of different widths
JWST sunshield, made of Kapton James Webb telescope sunshield.jpg
JWST sunshield, made of Kapton

Kapton is a polyimide film developed by DuPont in the late 1960s that remains stable across a wide range of temperatures, from −269 to +400 °C (−452 to 752 °F; 4 to 673 K). [1] [2] Kapton is used in, among other things, flexible printed circuits (flexible electronics) and thermal blankets used on spacecraft, satellites, and various space instruments.

Polyimide polymer of imide monomers

Polyimide is a polymer of imide monomers. Polyimides have been in mass production since 1955. With their high heat-resistance, polyimides enjoy diverse applications in roles demanding rugged organic materials, e.g. high temperature fuel cells, displays, and various military roles. A classic polyimide is Kapton, which is produced by condensation of pyromellitic dianhydride and 4,4'-oxydianiline.

DuPont American chemical company

DuPont de Nemours, Inc., commonly known as DuPont, is an American company formed by the merger of Dow Chemical and DuPont on August 31, 2017, and then subsequent spinoffs of Dow Inc. and Corteva. Prior to the spinoffs it was the world's largest chemical company in terms of sales. Within 18 months of the merger the company was split into three publicly traded companies with focuses on the following: agriculture, materials science, and specialty products. The agriculture division is named Corteva, the materials science spin-off is named Dow Inc., and the specialty products division is named DuPont. Jeff Fettig is executive chairman of the company, and Edward Breen is the CEO. The merger has been reported to be worth an estimated $130 billion. DowDuPont ranked No. 35 in the 2019 Fortune 500 list of the largest United States corporations by total revenue.

Flexible electronics

Flexible electronics, also known as flex circuits, is a technology for assembling electronic circuits by mounting electronic devices on flexible plastic substrates, such as polyimide, PEEK or transparent conductive polyester film. Additionally, flex circuits can be screen printed silver circuits on polyester. Flexible electronic assemblies may be manufactured using identical components used for rigid printed circuit boards, allowing the board to conform to a desired shape, or to flex during its use. An alternative approach to flexible electronics suggests various etching techniques to thin down the traditional silicon substrate to few tens of micrometers to gain reasonable flexibility, referred to as flexible silicon.


The chemical name for Kapton K and HN is poly (4,4'-oxydiphenylene-pyromellitimide). It is produced from the condensation of pyromellitic dianhydride and 4,4'-oxydiphenylamine. Kapton synthesis is an example of the use of a dianhydride in step polymerization. The intermediate polymer, known as a "poly(amic acid)", is soluble because of strong hydrogen bonds to the polar solvents usually employed in the reaction. The ring closure is carried out at high temperatures (200–300 °C (392–572 °F; 473–573 K)).

Pyromellitic dianhydride chemical compound

Pyromellitic dianhydride is an organic compound with the formula C6H2(C2O3)2. It is the double carboxylic acid anhydride that is used in the preparation of polyimide polymers such as Kapton. It is a white solid.

4,4-Oxydianiline chemical compound

4,4’-Oxydianiline is an organic compound with the formula O(C6H4NH2)2. It is an ether derivative of aniline. This colourless solid is a useful monomer and cross-linking agent for polymers, especially the polyimides, such as Kapton.

Hydrogen bond form of association between an electronegative atom and a hydrogen atom attached to a second,relatively electronegative atom;electrostatic interaction,heightened by the small size of hydrogen which permits proximity of the interacting dipoles/charges

A hydrogen bond is a primarily electrostatic force of attraction between a hydrogen (H) atom which is covalently bound to a more electronegative atom or group, particularly the second-row elements nitrogen (N), oxygen (O), or fluorine (F)—the hydrogen bond donor (Dn)—and another electronegative atom bearing a lone pair of electrons—the hydrogen bond acceptor (Ac). Such an interacting system is generally denoted Dn–H···Ac, where the solid line denotes a fully covalent bond, and the dotted or dashed line indicates the hydrogen bond. The use of three centered dots for the hydrogen bond is specifically recommended by the IUPAC. There is general agreement that there is actually a minor covalent component to hydrogen bonding, especially for moderate to strong hydrogen bonds, although the importance of covalency in hydrogen bonding is debated. At the opposite end of the scale, there is no clear boundary between a weak hydrogen bond and a van der Waals interaction.


The thermal conductivity of Kapton at temperatures from 0.5 to 5 kelvin is rather high for such low temperatures, κ = 4.638×10−3T0.5678 W·m−1·K−1. [3] This, together with its good dielectric qualities and its availability as thin sheets have made it a favorite material in cryogenics, as it provides electrical insulation at low thermal gradients. Kapton is regularly used as an insulator in ultra-high vacuum environments due to its low outgassing rate. [4]

Cryogenics study of the production and behaviour of materials at very low temperatures

In physics, cryogenics is the production and behaviour of materials at very low temperatures. A person who studies elements that have been subjected to extremely cold temperatures is called a cryogenicist.

Outgassing is the release of a gas that was dissolved, trapped, frozen or absorbed in some material. Outgassing can include sublimation and evaporation, as well as desorption, seepage from cracks or internal volumes, and gaseous products of slow chemical reactions. Boiling is generally thought of as a separate phenomenon from outgassing because it consists of a phase transition of a liquid into a vapor of the same substance.


Kapton-insulated electrical wiring has been widely used in civil and military aircraft because it is lighter than other insulators and has good insulating and temperature characteristics. However, Kapton insulation ages poorly: an FAA study shows degradation in hot, humid environments, [5] or in the presence of seawater. It was found to have very poor resistance to mechanical wear, mainly abrasion within cable harnesses due to aircraft movement. Many aircraft models have had to undergo extensive rewiring modifications—sometimes completely replacing all the Kapton-insulated wiring—because of short circuits caused by the faulty insulation. Kapton-wire degradation and chafing due to vibration and heat has been implicated in multiple crashes of both fixed wing and rotary wing aircraft, with loss of life. [6]


The descent stage of the Apollo Lunar Module, and the bottom of the ascent stage surrounding the ascent engine, were covered in blankets of aluminized Kapton foil to provide thermal insulation. During the return journey from the Moon, Apollo 11 astronaut Neil Armstrong commented that during the launch of the Lunar Module ascent stage, he could see "Kapton and other parts on the LM staging scattering all around the area for great distances." [7]

Apollo Lunar Module A lander used in the Apollo program.

The Apollo Lunar Module, or simply lunar module, originally designated the Lunar Excursion Module (LEM), was the lander spacecraft that was flown from lunar orbit to the Moon's surface during the U.S. Apollo program. It was the first manned spacecraft to operate exclusively in the airless vacuum of space, and remains the only crewed vehicle to land anywhere beyond Earth.

Apollo 11 First crewed mission to land on the Moon

Apollo 11 was the spaceflight that landed the first two people on the Moon. Commander Neil Armstrong and lunar module pilot Buzz Aldrin, both American, landed the Apollo Lunar Module Eagle on July 20, 1969, at 20:17 UTC. Armstrong became the first person to step onto the lunar surface six hours later on July 21 at 02:56:15 UTC; Aldrin joined him 19 minutes later. They spent about two and a quarter hours together outside the spacecraft, and collected 47.5 pounds (21.5 kg) of lunar material to bring back to Earth. Command module pilot Michael Collins flew the command module Columbia alone in lunar orbit while they were on the Moon's surface. Armstrong and Aldrin spent 21.5 hours on the lunar surface before rejoining Columbia in lunar orbit.

Neil Armstrong American astronaut; first person to walk on the moon

Neil Alden Armstrong was an American astronaut and aeronautical engineer who was the first person to walk on the Moon. He was also a naval aviator, test pilot, and university professor.

According to a NASA internal report, space shuttle "wires were coated with an insulator known as Kapton that tended to break down over time, causing short circuits and, potentially, fires." [8] The NASA Jet Propulsion Laboratory has considered Kapton as a good plastic support for solar sails because of its long duration in the space environment. [9]

NASA space-related agency of the United States government

The National Aeronautics and Space Administration is an independent agency of the United States Federal Government responsible for the civilian space program, as well as aeronautics and aerospace research.

Space Shuttle program United States governments manned launch vehicle program, administered by NASA from 1972 to 2011

The Space Shuttle program was the fourth human spaceflight program carried out by the National Aeronautics and Space Administration (NASA), which accomplished routine transportation for Earth-to-orbit crew and cargo from 1981 to 2011. Its official name, Space Transportation System (STS), was taken from a 1969 plan for a system of reusable spacecraft of which it was the only item funded for development.

Jet Propulsion Laboratory Research and development center and NASA field center in California, US

The Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center in La Cañada Flintridge, California, United States, though it is often referred to as residing in Pasadena, California, because it has a Pasadena ZIP Code.

NASA's New Horizons spacecraft used Kapton in an innovative "Thermos bottle" insulation design to keep the craft operating between 10–30 °C (50–86 °F) throughout its more than nine-year, 3 billion mile journey to rendezvous with the dwarf planet Pluto on July 14, 2015. [10] The main body is covered in lightweight, gold-colored, multilayered thermal insulation which holds in heat from operating electronics to keep the spacecraft warm. The thermal blanketing–18 layers of Dacron mesh cloth sandwiched between aluminized Mylar and Kapton film–also helped to protect the craft from micrometeorites. [11]

The sunshield of the James Webb Space Telescope is also made of aluminized Kapton. [12]

The crew aboard the International Space Station used Kapton tape to temporarily repair a slow leak in a Soyuz spacecraft attached to the Russian segment of the orbital complex in August, 2018. [13]


Kapton is also commonly used as a material for windows of all kinds at X-ray sources (synchrotron beam-lines and X-ray tubes) and X-ray detectors. Its high mechanical and thermal stability and high transmittance to X-rays make it the preferred material. It is also relatively insensitive to radiation damage. [14]

Electronics manufacturing

Kapton tape (yellow) used to insulate the leads of a battery cell in a bluetooth headset. Kapton Tape.png
Kapton tape (yellow) used to insulate the leads of a battery cell in a bluetooth headset.

Due to its large range of temperature stability, and its electrical isolation ability, Kapton tape is usually used in electronic manufacturing as an insulation and protection layer on electrostatic sensitive and fragile components. As it can sustain the temperature needed for a reflow soldering operation, its protection is available throughout the whole production process, and Kapton is often still present in the final consumer product.

3D printing

Kapton and ABS adhere to each other very well, which has led to widespread use of Kapton as a build surface for 3D printers. Kapton is laid down on a flat surface and the ABS is extruded onto the Kapton surface. The ABS part being printed will not detach from the build platform as it cools and shrinks, a common cause of print failure by warping of the part.[ citation needed ]


Kapton is a registered trademark of E. I. du Pont de Nemours and Company. [15]

Related Research Articles

Insulator (electricity) material whose internal electric charges do not flow freely, and which therefore does not conduct an electric current

An electrical insulator is a material whose internal electric charges do not flow freely; very little electric current will flow through it under the influence of an electric field. This contrasts with other materials, semiconductors and conductors, which conduct electric current more easily. The property that distinguishes an insulator is its resistivity; insulators have higher resistivity than semiconductors or conductors.

Thermal insulation technique used to minimize the heating demand of buildings

Thermal insulation is the reduction of heat transfer between objects in thermal contact or in range of radiative influence. Thermal insulation can be achieved with specially engineered methods or processes, as well as with suitable object shapes and materials.

A heat shield is a part of an object designed to protect the object from overheating by dissipating, reflecting or simply absorbing the heat. The term is most often used in reference to exhaust heat management and to systems for dissipation of heat due to friction.

Radiant barrier

A radiant barrier is a type of building product that reflects thermal radiation and reduces heat transfer. Since thermal energy is also transferred via conduction and convection, radiant barriers are often supplemented with thermal insulation products that slow down heat transfer via conduction or convection.

Space Shuttle thermal protection system Space Shuttle heat shielding system

The Space Shuttle thermal protection system (TPS) is the barrier that protected the Space Shuttle Orbiter during the searing 1,650 °C (3,000 °F) heat of atmospheric reentry. A secondary goal was to protect from the heat and cold of space while in orbit.

Space blanket

A space blanket is an especially low-weight, low-bulk blanket made of heat-reflective thin plastic sheeting. They are used on the exterior surfaces of spacecraft for thermal control, as well as by people. Their design reduces the heat loss in a person's body, which would otherwise occur due to thermal radiation, water evaporation, or convection. Their compact size before unfurling and light weight makes them ideal when space or weight are at a premium. They may be included in first aid kits and also in camping equipment. Lost campers and hikers have an additional possible benefit: the metallic surface appearance flashes in the sun, allowing use as an improvised distress beacon for searchers and also as a method of signalling over long distances to other people on the same route as the person who owns the blanket.

Vespel is the trademark of a range of durable high-performance polyimide-based plastics manufactured by DuPont. The one shown in the structure on the right was the first to be commercialized.

Magnet wire

Magnet wire or enameled wire is a copper or aluminium wire coated with a very thin layer of insulation. It is used in the construction of transformers, inductors, motors, speakers, hard disk head actuators, electromagnets, and other applications that require tight coils of insulated wire.

Building insulation material used to thermally insulate buildings

Building insulation is any object in a building used as insulation for any purpose. While the majority of insulation in buildings is for thermal purposes, the term also applies to acoustic insulation, fire insulation, and impact insulation. Often an insulation material will be chosen for its ability to perform several of these functions at once.

Polyimide foam is a foam originally designed for NASA by Inspec Foams Inc. under the brand name Solimide. Its primary purposes are as an insulator and acoustic damper. NASA engineered the product to have relatively low outgassing, desirable thermal and acoustic performance, as well as uniformity during distribution and application. Typical uses of the foam include ducting, duct/piping insulation, structural components, and strengthening of hollow components while remaining lightweight. In addition to thermal and acoustic properties, polyimide foam is fire resistant, lightweight and non-toxic.

Multi-layer insulation

Multi-layer insulation, or MLI, is thermal insulation composed of multiple layers of thin sheets and is often used on spacecraft. It is one of the main items of the spacecraft thermal design, primarily intended to reduce heat loss by thermal radiation. In its basic form, it does not appreciably insulate against other thermal losses such as heat conduction or convection. It is therefore commonly used on satellites and other applications in vacuum where conduction and convection are much less significant and radiation dominates. MLI gives many satellites and other space probes the appearance of being covered with gold foil.

Thermal Micrometeoroid Garment outer, protective layer of a spacesuit

An (Integrated) Thermal Micrometeoroid Garment is the outer layer of a space suit. The TMG has three functions: to insulate the suit occupant and prevent heat loss, to shield the occupant from harmful solar radiation, and to protect the astronaut from micrometeoroids and other orbital debris, which could puncture the suit and depressurize it.

Insulated shipping containers are a type of packaging used to ship temperature sensitive products such as foods, pharmaceuticals, organs, blood, biologic materials, and chemicals. They are used as part of a cold chain to help maintain product freshness and efficacy. The term can also refer to insulated intermodal containers or insulated swap bodies.

Upilex is a heat-resistant polyimide film that is the product of the polycondensation reaction between biphenyl tetracarboxylic dianhydride (BPDA) monomers and diamine. Its properties include dimensional stability, low water absorption, high chemical resistance and high mechanical properties, high heat and chemical resistance. It was developed by UBE Industries. Upilex-S is the standard grade but other grades include Upilex-RN, VT, CA and SGA. Upilex-S is used when excellent mechanical properties are required, Upilex-RN possesses excellent molding processability, while Upilex-VT has superior heat bonding characteristics. General applications of Upilex include their use in flexible printed circuits, electric motor and generator insulation, high temperature wire and cable wrapping, and specialty pressure sensitive tapes. Polyimides have also been extensively studied in gas and humidity sensors. The concentration is then determined by monitoring the capacitance of modified Upilex films. With the advantages of flexibility and easy functionalization, Upilex films are often used as substrate materials in biosensor platforms. For instance, it is possible to electropolymerize onto these films or attach enzymes to it for the detection of glucose.

Spacecraft thermal control process of keeping all parts of a spacecraft within acceptable temperature ranges

In spacecraft design, the function of the thermal control system (TCS) is to keep all the spacecraft's component systems within acceptable temperature ranges during all mission phases. It must cope with the external environment, which can vary in a wide range as the spacecraft is exposed to deep space or to solar or planetary flux, and with ejecting to space the internal heat generated by the operation of the spacecraft itself.

Integrated Science Instrument Module

Integrated Science Instrument Module (ISIM) is a component of the James Webb Space Telescope, a large international infrared space telescope planned for launch in spring 2021. ISIM is the heart of the JWST, and holds the main science payload which includes four science instruments and the fine guidance sensor. ISIM is the spacecraft chassis and instruments that take the light from the main mirror and convert that into the science data that is then sent back to Earth. The other two major sections of the JWST are the Optical Telescope Element (OTE) and the Spacecraft Element (SE), which includes the Spacecraft Bus and Sunshield. ISIM has a mass of 1.4 metric tons (tonnes). The infrared camera instrument integrated with ISIM passed its thermal tests in early 2016. ISIM underwent intense thermal cold testing in late 2015 to early 2016. NIRcam is extremely important to JWST, because it's not only a sensitive infrared camera, but it is also used to adjust the alignment of the main mirror segments. The tests were very positive because NIRcam showed was very stable through vibration and thermal testing. NIRcam was installed into ISIM in March 2014, and then underwent integration and testing after that, as the telescope is readied for its 2019 launch. ISIM is about 23% of the overall mass of JWST, which equates to an ISIM mass of 1400 kg.

Optical Telescope Element

Optical Telescope Element (OTE) is a sub-section of the James Webb Space Telescope, a large infrared space telescope scheduled to be launched early 2021. The OTE consists of some major parts of the telescopes including the main mirror, the secondary mirrors, the framework and controls to support those mirrors, and various thermal and other systems to support the functioning of the telescope. The other two major sections of the JWST are the Integrated Science Instrument Module and the Spacecraft Element (SE), which includes the Spacecraft Bus and Sunshield. The OTE collects the light and sends it to the science instruments in the ISIM. The OTE has been compared to being the "eye" of the telescope and the backplane of it to being the "spine".

Sunshield (JWST) component of the James Webb Space Telescope

Sunshield is a component of the James Webb Space Telescope, designed to shield the main optics from the Sun's heat and light. This is part of a space telescope and it extends out unfolding a large metal-coated sheet of material post-launch. This material blocks the Sun's light and heat, so the telescope can see the faint light coming from stars and galaxies. The sunshield segment includes the layers and its deployment mechanisms, which also includes the trim flap.


  1. "DuPont Circuit & Packaging Materials Awarded U.S. Patents for Matte Black Film and Coverlay". November 15, 2013. Retrieved 2015-05-28. DuPont invented Kapton® polyimide film over 45 years ago
  2. Navick, X.-F.; Carty, M.; Chapellier, M.; Chardin, G.; Goldbach, C.; Granelli, R.; Hervé, S.; Karolak, M.; Nollez, G.; Nizery, F.; Riccio, C.; Starzynski, P.; Villar, V. (2004). "Fabrication of ultra-low radioactivity detector holders for Edelweiss-II". Nuclear Instruments and Methods in Physics Research Section A. 520: 189–192. doi:10.1016/j.nima.2003.11.290.
  3. Jason Lawrence, A. B. Patel and J. G. Brisson (2000). "The thermal conductivity of Kapton HN between 0.5 and 5 K". Cryogenics. 40 (3): 203–207. doi:10.1016/S0011-2275(00)00028-X.
  4. Peter Kittel (30 September 1998). Advances in Cryogenic Engineering. Birkhäuser. pp. 1366–. ISBN   978-0-306-45807-1 . Retrieved 29 April 2012.
  5. FAA insulation ageing test results. DOT/FAA Tech Report AR-08/2, January 2008. Retrieved on 2013-08-23
  6. Fatal helicopter crash caused by Kapton wiring www.military.com Retrieved 2015-02-17.
  7. Apollo 11 Flight Journal – Day 6 part 4: Trans-Earth Injection. History.nasa.gov (2011-03-15). Retrieved on 2012-04-28.
  8. High Tech in the 1970s, Shuttles Feel Their Age. New York Times (2005-07-25)
  9. Jerome L. Wright (1 January 1992). Space Sailing. Taylor & Francis US. pp. 100–. ISBN   978-2-88124-842-9 . Retrieved 28 April 2012.
  10. NASA New Horizons Pluto Mission, Mission Design Retrieved April 23, 2015
  11. NASA, New Horizons Mission, Thermal Control
  12. "Sunshield Membrane Coatings" page at the JWST website. Ngst.gsfc.nasa.gov. Retrieved on 2017-05-23.
  13. "ISS Status blog" at NASA website. blogs.nasa.gov/spacestation/2018/08/30/international-space-station-status-2/ Retrieved on 2018-08-30.
  14. Janez Megusar (1997). "Low temperature fast-neutron and gamma irradiation of Kapton polyimide films". Journal of Nuclear Materials. 245 (2–3): 185–190. doi:10.1016/S0022-3115(97)00012-3.
  15. "Kapton Trademark". United States Patent and Trademark Office. USPTO. Retrieved 3 March 2017.