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Polyurethane
Polyurethane (; often abbreviated PUR and PU) is a class of polymers composed of organic chemistry, organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane term does not refer to the single type of polymer but a group of polymers. Unlike polyethylene and polystyrene, polyurethanes can be produced from a wide range of starting materials resulting in various polymers within the same group. This chemical variety produces polyurethanes with different chemical structures leading to many List of polyurethane applications, different applications. These include rigid and flexible foams, and coatings, adhesives, Potting (electronics), electrical potting compounds, and fibers such as spandex and polyurethane laminate (PUL). Foams are the largest application accounting for 67% of all polyurethane produced in 2016. A polyurethane is typically produced by reacting a polymeric isocyanate with a polyol. Since a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Polyurethane Applications
Polyurethane products have many uses. Over three quarters of the global consumption of polyurethane products is in the form of foams, with flexible and rigid types being roughly equal in market size. In both cases, the foam is usually behind other materials: flexible foams are behind upholstery fabrics in commercial and domestic furniture; rigid foams are between metal, or plastic walls/sheets of most refrigerators and freezers, or other surface materials in the case of thermal insulation panels in the construction sector. Its use in garments is growing: for example, in lining the cups of brassieres. Polyurethane is also used for moldings which include door frames, columns, balusters, window headers, pediments, medallions and rosettes. Polyurethane formulations cover an extremely wide range of stiffness, hardness, and densities. These materials include: * Low-density flexible foam used in upholstery, bedding, automotive and truck seating, and novel inorganic plant substrates f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyol
In organic chemistry, a polyol is an organic compound containing multiple hydroxyl groups (). The term "polyol" can have slightly different meanings depending on whether it is used in food science or polymer chemistry. Polyols containing two, three and four hydroxyl groups are diols, triols, and tetrols, respectively. Classification Polyols may be classified according to their chemistry. Some of these chemistries are polyether, polyester, polycarbonate and also acrylic polyols. Polyether polyols may be further subdivided and classified as polyethylene oxide or polyethylene glycol (PEG), polypropylene glycol (PPG) and Polytetrahydrofuran or PTMEG. These have 2, 3 and 4 carbons respectively per oxygen atom in the repeat unit. Polycaprolactone polyols are also commercially available. There is also an increasing trend to use biobased (and hence renewable) polyols. Uses Polyether polyols have numerous uses. As an example, polyurethane foam is a big user of polyether polyols. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyisocyanate
In organic chemistry, isocyanate is the functional group with the formula . Organic compounds that contain an isocyanate group are referred to as isocyanates. An organic compound with two isocyanate groups is known as a diisocyanate. Diisocyanates are manufactured for the production of polyurethanes, a class of polymers. Isocyanates should not be confused with cyanate esters and isocyanides, very different families of compounds. The cyanate (cyanate ester) functional group () is arranged differently from the isocyanate group (). Isocyanides have the connectivity , lacking the oxygen of the cyanate groups. Structure and bonding In terms of bonding, isocyanates are closely related to carbon dioxide (CO2) and carbodiimides (C(NR)2). The C−N=C=O unit that defines isocyanates is planar, and the N=C=O linkage is nearly linear. In phenyl isocyanate, the C=N and C=O distances are respectively 1.195 and 1.173 Å. The C−N=C angle is 134.9° and the N=C=O angle is 173.1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbamate
In organic chemistry, a carbamate is a category of organic compounds with the general Chemical formula, formula and Chemical structure, structure , which are formally Derivative (chemistry), derived from carbamic acid (). The term includes organic compounds (e.g., the ester ethyl carbamate), formally obtained by replacing one or more of the hydrogen atoms by other organic functional groups; as well as salt (chemistry), salts with the carbamate anion (e.g. ammonium carbamate). Polymers whose repeat units are joined by carbamate like groups are an important family of plastics, the polyurethanes. See for clarification. Properties While carbamic acids are unstable, many carbamate esters and salt (chemistry), salts are stable and well known. Equilibrium with carbonate and bicarbonate In water solutions, the carbamate anion slowly equilibrates with the ammonium cation and the carbonate or bicarbonate anions: : : Calcium carbamate is soluble in water, whereas calcium carbona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyurethane Laminate
Polyurethane laminate (PUL, thermal stretch, fuzzy rubber) is a compound fabric made by laminating a cloth fabric to one or both sides of a thin film of polyurethane. Polyurethane laminated fabrics have a wide range of applications in medical, automotive and garment uses. Most PUL fabric is made by laminating lightweight polyester interlock knit fabric to a 1mm thick film of polyurethane. There are two processes used for lamination: solvent lamination, which fuses the fabric and polyurethane film into a single monolithic fabric, and hot melt, which uses heat-activated glue to adhere the fabrics together. Woven fabric and fleece fabric can also be used, but a stiff fabric will drastically reduce the elasticity of the finished laminate. Use PU laminate cloth is waterproof, breathes and stretches somewhat, and is soft and flexible. It can usually be machine-washed and dried, and cleaned with dilute bleach or alcohol. PU fabric is useful as a wind and/or water barrier in the const ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poly(tetramethylene Ether) Glycol
Polytetrahydrofuran, also called poly(tetramethylene ether) glycol or poly(tetramethylene oxide), is a collection of chemical compounds with formula or HO((CH2)4O-)''n''-H. The material is a mixture of polyether diols terminated with alcohol groups. It is produced by polymerization of tetrahydrofuran as well as 1,4-butanediol. The product is commercially available as polymers of low average molecular weights, between 250 and 3000 daltons. In this form it is a white waxy solid that melts between 20 and 30 °C. The commercial product can be processed further into polymers with molecular weights of 40,000 and higher. The product is sold under various trade names including Terathane from Invista and PolyTHF from BASF. The BASF plant in Ludwigshafen at one point was producing 250,000 metric tons per year. Applications The main use of polytetrahydrofuran is to make elastic fibres such as spandex (elastane) for stretchable fabrics and for polyurethane resins. The latter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IG Farben
I. G. Farbenindustrie AG, commonly known as IG Farben, was a German Chemical industry, chemical and Pharmaceutical industry, pharmaceutical conglomerate (company), conglomerate. It was formed on December 2, 1925 from a merger of six chemical companies: Agfa-Gevaert, Agfa, BASF, Bayer, :de:Chemische Fabrik Griesheim-Elektron, Griesheim-Elektron, Hoechst AG, Hoechst, and Weiler-ter-Meer. It was seized by the Allies of World War II, Allies after World War II and split into its constituent companies; parts in East Germany were nationalized. IG Farben was once the largest company in Europe and the largest chemical and pharmaceutical company in the world. IG Farben scientists made fundamental contributions to all areas of chemistry and the pharmaceutical industry. Otto Bayer discovered the polyaddition for the synthesis of polyurethane in 1937, and three company scientists became List of Nobel laureates, Nobel laureates: Carl Bosch and Friedrich Bergius in 1931 "for their contribution ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dow Chemical
The Dow Chemical Company is an American multinational corporation headquartered in Midland, Michigan, United States. The company was among the three largest chemical producers in the world in 2021. It is the operating subsidiary of Dow Inc., a publicly traded holding company incorporated under Delaware law. With a presence in around 160 countries, it employs about 36,000 people worldwide. Dow has been called the "chemical companies' chemical company", as its sales are to other industries rather than directly to end-use consumers. Dow is a member of the American Chemistry Council. In 2015, Dow and fellow chemical company DuPont agreed to a corporate reorganization involving the merger of Dow and DuPont followed by a separation into three different entities. The plan commenced in 2017, when Dow and DuPont merged to form DowDuPont, and was finalized in April 2019, when the materials science division was spun off from DowDuPont and took the name of the Dow Chemical Company. Hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyester
Polyester is a category of polymers that contain one or two ester linkages in every repeat unit of their main chain. As a specific material, it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include some naturally occurring chemicals, such as those found in plants and insects. Natural polyesters and a few synthetic ones are biodegradable, but most synthetic polyesters are not. Synthetic polyesters are used extensively in clothing. Polyester fibers are sometimes spun together with natural fibers to produce a cloth with blended properties. Cotton-polyester blends can be strong, wrinkle- and tear-resistant, and reduce shrinking. Synthetic fibers using polyester have high water, wind, and environmental resistance compared to plant-derived fibers. They are less Fireproofing, fire-resistant and can melt when ignited. Liquid crystalline polyesters are among the first industrially used liquid crystal polymers. They are used for their mechanical propert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otto Bayer
Otto Bayer (4 November 1902 – 1 August 1982) was a German industrial chemist at IG Farben who was head of the research group that in 1937 discovered the polyaddition for the synthesis of polyurethanes out of poly-isocyanate and polyol. Bayer was not related to the founding family of Bayer Corp. Today polyurethanes are ubiquitous throughout modern life. He was a member of the board of directors and of the supervisory board of Bayer, and was also vice chairman of the supervisory board of Cassella in the 1950s. Bayer was the 1975 recipient of the Charles Goodyear Medal The Charles Goodyear Medal is the highest honor conferred by the American Chemical Society#Organization, American Chemical Society, Rubber Division. Established in 1941, the award is named after Charles Goodyear, the discoverer of vulcanization, .... He was the 1974 recipient of the Carl-Dietrich-Harries-Medal for commendable scientific achievements. References 1902 births 1982 deaths 20th-centu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
