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Kapton
Structure of poly-oxydiphenylene-pyromellitimide Kapton insulating pads for mounting electronic parts on a heat sink Kapton is a polyimide film used in flexible printed circuits ( flexible electronics) and space blankets, which are used on spacecraft, satellites, and various space instruments. Invented by the DuPont Corporation in the 1960s, Kapton remains stable (in isolation) across a wide range of temperatures, from . History Kapton was invented by the DuPont Corporation in the 1960s. The name ''Kapton'' is a registered trademark of E. I. du Pont de Nemours and Company. Chemistry and variants 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 of . The chemical name for Kapton K and HN is ''poly (4,4'-oxydiphenylene-pyromelli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kapton Tape
Structure of poly-oxydiphenylene-pyromellitimide Kapton insulating pads for mounting electronic parts on a heat sink Kapton is a polyimide film used in flexible printed circuits (flexible electronics) and space blankets, which are used on spacecraft, satellites, and various space instruments. Invented by the DuPont Corporation in the 1960s, Kapton remains stable (in isolation) across a wide range of temperatures, from . History Kapton was invented by the DuPont Corporation in the 1960s. The name ''Kapton'' is a registered trademark of E. I. du Pont de Nemours and Company. Chemistry and variants 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 of . The chemical name for Kapton K and HN is ''poly (4,4'-oxydiphenylene-pyromellit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kapton Tapes, Three Rolls Of Different Widths
Structure of poly-oxydiphenylene-pyromellitimide Kapton insulating pads for mounting electronic parts on a heat sink Kapton is a polyimide film used in flexible printed circuits (flexible electronics) and space blankets, which are used on spacecraft, satellites, and various space instruments. Invented by the DuPont Corporation in the 1960s, Kapton remains stable (in isolation) across a wide range of temperatures, from . History Kapton was invented by the DuPont Corporation in the 1960s. The name ''Kapton'' is a registered trademark of E. I. du Pont de Nemours and Company. Chemistry and variants 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 of . The chemical name for Kapton K and HN is ''poly (4,4'-oxydiphenylene-pyromellit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyimide
Polyimide (sometimes abbreviated PI) is a polymer containing imide groups belonging to the class of high-performance plastics. 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.Wright, Walter W. and Hallden-Abberton, Michael (2002) "Polyimides" in ''Ullmann's Encyclopedia of Industrial Chemistry'', Wiley-VCH, Weinheim. History The first polyimide was discovered in 1908 by Bogart and Renshaw. They found that 4-amino phthalic anhydride does not melt when heated but does release water upon the formation of a high molecular weight polyimide. The first semialiphatic polyimide was prepared by Edward and Robinson by melt fusion of diamines and tetra acids or diamines and diacids / diester. However, the first polyimide of significan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coefficient Of Thermal Expansion
Thermal expansion is the tendency of matter to change its shape, area, volume, and density in response to a change in temperature, usually not including phase transitions. Temperature is a monotonic function of the average molecular kinetic energy of a substance. When a substance is heated, molecules begin to vibrate and move more, usually creating more distance between themselves. Substances which contract with increasing temperature are unusual, and only occur within limited temperature ranges (see examples below). The relative expansion (also called strain) divided by the change in temperature is called the material's coefficient of linear thermal expansion and generally varies with temperature. As energy in particles increases, they start moving faster and faster weakening the intermolecular forces between them, therefore expanding the substance. Overview Predicting expansion If an equation of state is available, it can be used to predict the values of the thermal ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Sail
Solar sails (also known as light sails and photon sails) are a method of spacecraft propulsion using radiation pressure exerted by sunlight on large mirrors. A number of spaceflight missions to test solar propulsion and navigation have been proposed since the 1980s. The first spacecraft to make use of the technology was IKAROS, launched in 2010. A useful analogy to solar sailing may be a sailing boat; the light exerting a force on the mirrors is akin to a sail being blown by the wind. High-energy laser beams could be used as an alternative light source to exert much greater force than would be possible using sunlight, a concept known as beam sailing. Solar sail craft offer the possibility of low-cost operations combined with long operating lifetimes. Since they have few moving parts and use no propellant, they can potentially be used numerous times for delivery of payloads. Solar sails use a phenomenon that has a proven, measured effect on astrodynamics. Solar pressure aff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Blanket
A space blanket (also known as a Mylar blanket, emergency blanket, first aid blanket, safety blanket, thermal blanket, weather blanket, heat sheet, foil blanket, or shock 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 low weight and compact size before unfurling make them ideal when space or weight are at a premium. They may be included in first aid kits and with camping equipment. Lost campers and hikers have an additional possible benefit: the shiny surface flashes in the sun, allowing its use as an improvised distress beacon for searchers and as a method of signalling over long distances to other people. Manufacturing First developed by NASAs Marshall Space Flight Center in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DuPont (1802-2017)
DuPont de Nemours, Inc., commonly shortened to DuPont, is an American multinational chemical company first formed in 1802 by French-American chemist and industrialist Éleuthère Irénée du Pont de Nemours. The company played a major role in the development of Delaware and first arose as a major supplier of gunpowder. DuPont developed many polymers such as Vespel, neoprene, nylon, Corian, Teflon, Mylar, Kapton, Kevlar, Zemdrain, M5 fiber, Nomex, Tyvek, Sorona, Corfam and Lycra in the 20th century, and its scientists developed many chemicals, most notably Freon (chlorofluorocarbons), for the refrigerant industry. It also developed synthetic pigments and paints including ChromaFlair. In 2015, DuPont and the Dow Chemical Company agreed to a reorganization plan in which the two companies would merge and split into three. As a merged entity, DuPont simultaneously acquired Dow and renamed itself to DowDuPont on August 31, 2017, and after 18 months spin off the merged entity's ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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. Manufacturing Flexible printed circuits (FPC) are made with a photolithographic technology. An alternative way of making flexible foil circuits or flexible flat cables (FFCs) is laminating very thin (0.07 mm) copper strips in between two layers of PET. These PET layers, typically 0.05 mm thick, are coated with an adhesive which is thermosetting, and will be activated during the lamination process. FPCs and FFCs have several advantages in many applications: * Tightl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apollo Lunar Module
The Apollo Lunar Module (LM ), originally designated the Lunar Excursion Module (LEM), was the lunar lander spacecraft that was flown between lunar orbit and the Moon's surface during the United States' Apollo program. It was the first crewed spacecraft to operate exclusively in the airless vacuum of space, and remains the only crewed vehicle to land anywhere beyond Earth. Structurally and aerodynamically incapable of flight through Earth's atmosphere, the two-stage lunar module was ferried to lunar orbit attached to the Apollo command and service module (CSM), about twice its mass. Its crew of two flew the complete lunar module from lunar orbit to the Moon's surface. During takeoff, the spent descent stage was used as a launch pad for the ascent stage which then flew back to the command module, after which it was also discarded. Overseen by Grumman, the LM's development was plagued with problems that delayed its first uncrewed flight by about ten months and its first cre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyromellitic Dianhydride
Pyromellitic dianhydride (PMDA) 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, hygroscopic solid. It forms a hydrate. Preparation It is prepared by gas-phase oxidation of 1,2,4,5-tetramethylbenzene (or related tetrasubstituted benzene derivatives). An idealized equation is: :C6H2(CH3)4 + 6 O2 → C6H2(C2O3)2 + 6 H2O In the laboratory, it can be prepared by dehydration of pyromellitic acid using acetic anhydride. Reactions PMDA is an electron-acceptor, forming a variety of charge-transfer complex In chemistry, a charge-transfer (CT) complex or electron-donor-acceptor complex describes a type of supramolecular assembly of two or more molecules or ions. The assembly consists of two molecules that self-attract through electrostatic forc ...es. It reacts with amines to diimides, C6H2 CO)2NRsub>2 which also have acceptor propertie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
4,4'-Oxydianiline
4,4′-Oxydianiline (ODA) is an organic compound with the formula O( C6 H4 NH2)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. Uses 4,4′-Oxydianiline is used in the production of a wide variety of polymer resins. The primary use lies in the production of polyimide and poly(ester)imide resins. These resins are used for their temperature-resistant properties and are utilized in products including wire enamels, coatings, film, adhesives, insulating varnishes, coated fabrics, flame-retardant fibers, oil sealants and retainers, insulation for cables and printed circuits, and laminates and composite for aerospace vehicles. Other applications of 4,4′-oxydianiline include the production of poly(amide)imide resins (which are used in the manufacture of heat-resistant wire enamels and coatings), as an intermediate in the manufacture of epoxy resins and adhesives, and in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
