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Aramid Fiber
Aramid fibers, short for aromatic polyamide, are a class of heat-resistant and strong synthetic fibers. They are used in aerospace and military applications, for ballistic-rated body armor fabric and ballistic composites, in marine cordage, marine hull reinforcement, and as an asbestos substitute. The chain molecules in the fibers are highly oriented along the fiber axis. As a result, a higher proportion of the chemical bond contributes more to fiber strength than in many other synthetic fibers. Aramids have a very high melting point (>500 °C). Common aramid brand names include Kevlar, Nomex, and Twaron. Terminology and chemical structure ''Aramid'' is a shortened form of aromatic polyamide. The term was introduced in 1972, accepted in 1974 by the Federal Trade Commission of the USA as the name of a generic category of fiber distinct from nylon, and adopted by the International Standards Organisation in 1977. Aromatic in the name refers to the presence of aromatic rin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synthetic Fiber
Synthetic fibers or synthetic fibres (in British English; see spelling differences) are fibers made by humans through chemical synthesis, as opposed to natural fibers that are directly derived from living organisms, such as plants (like cotton) or fur from animals. They are the result of extensive research by scientists to replicate naturally occurring animal and plant fibers. In general, synthetic fibers are created by extruding fiber-forming materials through spinnerets, forming a fiber. These are called synthetic or artificial fibers. The word polymer comes from a Greek prefix "poly" which means "many" and suffix "mer" which means "single units". (Note: each single unit of a polymer is called a monomer). Early experiments The first fully synthetic fiber was glass. Joseph Swan invented one of the first artificial fibers in the early 1880s; today it would be called semisynthetic in precise usage. His fiber was drawn from a cellulose liquid, formed by chemically modifyi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aromaticity
In chemistry, aromaticity is a chemical property of cyclic ( ring-shaped), ''typically'' planar (flat) molecular structures with pi bonds in resonance (those containing delocalized electrons) that gives increased stability compared to saturated compounds having single bonds, and other geometric or connective non-cyclic arrangements with the same set of atoms. Aromatic rings are very stable and do not break apart easily. Organic compounds that are not aromatic are classified as aliphatic compounds—they might be cyclic, but only aromatic rings have enhanced stability. The term ''aromaticity'' with this meaning is historically related to the concept of having an aroma, but is a distinct property from that meaning. Since the most common aromatic compounds are derivatives of benzene (an aromatic hydrocarbon common in petroleum and its distillates), the word ''aromatic'' occasionally refers informally to benzene derivatives, and so it was first defined. Nevertheless, many ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rayon
Rayon is a semi-synthetic fiber, made from natural sources of regenerated cellulose, such as wood and related agricultural products. It has the same molecular structure as cellulose. It is also called viscose. Many types and grades of viscose fibers and films exist. Some imitate the feel and texture of natural fibers such as silk, wool, cotton, and linen. The types that resemble silk are often called artificial silk. The fibre is used to make textiles for clothing and other purposes. Rayon production involves solubilizing cellulose to allow turning the fibers into required form. Three common ways to solubilize are the cuprammonium process, not in use today, using ammoniacal solutions of copper salts; the viscose process, the most common today, using alkali and carbon sulfide; and the Lyocell process, using amine oxide. The last avoids the neurotoxic carbon sulfide of the viscose process but is also more expensive. Rayon and its variants Rayon is produced by dissolving c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AkzoNobel
Akzo Nobel N.V., stylized as AkzoNobel, is a Dutch multinational company which creates paints and performance coatings for both industry and consumers worldwide. Headquartered in Amsterdam, the company has activities in more than 80 countries, and employs over 32,000 people. Sales in 2020 were €8.5 billion. History AkzoNobel has a long history of mergers and divestments. Parts of the current company can be traced back to 17th-century companies. The milestone mergers and divestments are the formation of AKZO in 1969, the merger with Nobel Industries in 1994 forming Akzo Nobel, and the divestment of its pharmaceutical business and the merger with ICI in 2007/2008 resulting in current-day AkzoNobel. History and formation of Akzo Akzo was formed in 1969 as merger of Algemene Kunstzijde Unie (AKU) and Koninklijke Zout Organon (KZO). The AKU was formed in 1929 when the Vereinigte Glanzstoff Fabrike (est. 1899) and Nederlandse Kunstzijdefabriek (ENKA, est. 1911) merged, forming A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elastic Modulus
An elastic modulus (also known as modulus of elasticity) is the unit of measurement of an object's or substance's resistance to being deformed elastically (i.e., non-permanently) when a stress is applied to it. The elastic modulus of an object is defined as the slope of its stress–strain curve in the elastic deformation region: A stiffer material will have a higher elastic modulus. An elastic modulus has the form: :\delta \ \stackrel\ \frac where stress is the force causing the deformation divided by the area to which the force is applied and strain is the ratio of the change in some parameter caused by the deformation to the original value of the parameter. Since strain is a dimensionless quantity, the units of \delta will be the same as the units of stress. Specifying how stress and strain are to be measured, including directions, allows for many types of elastic moduli to be defined. The three primary ones are: # ''Young's modulus'' (E) describes tensile and compressive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tensile Strength
Ultimate tensile strength (UTS), often shortened to tensile strength (TS), ultimate strength, or F_\text within equations, is the maximum stress that a material can withstand while being stretched or pulled before breaking. In brittle materials the ultimate tensile strength is close to the yield point, whereas in ductile materials the ultimate tensile strength can be higher. The ultimate tensile strength is usually found by performing a tensile test and recording the engineering stress versus strain. The highest point of the stress–strain curve is the ultimate tensile strength and has units of stress. The equivalent point for the case of compression, instead of tension, is called the compressive strength. Tensile strengths are rarely of any consequence in the design of ductile members, but they are important with brittle members. They are tabulated for common materials such as alloys, composite materials, ceramics, plastics, and wood. Definition The ultimate tensile st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Para- (chemistry)
Arene substitution patterns are part of organic chemistry IUPAC nomenclature and pinpoint the position of substituents other than hydrogen in relation to each other on an aromatic hydrocarbon. ''Ortho'', ''meta'', and ''para'' substitution * In ''ortho''-substitution, two substituents occupy positions next to each other, which may be numbered 1 and 2. In the diagram, these positions are marked R and ''ortho''. * In ''meta''-substitution the substituents occupy positions 1 and 3 (corresponding to R and ''meta'' in the diagram). * In ''para''-substitution, the substituents occupy the opposite ends (positions 1 and 4, corresponding to R and ''para'' in the diagram). The toluidines serve as an example for these three types of substitution. Synthesis Electron donating groups, for example amino, hydroxyl, alkyl, and phenyl groups tend to be ''ortho''/''para''-directors, and electron withdrawing groups such as nitro, nitrile, and ketone groups, tend to be ''meta''-directors. Pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bayer
Bayer AG (, commonly pronounced ; ) is a German multinational pharmaceutical and biotechnology company and one of the largest pharmaceutical companies in the world. Headquartered in Leverkusen, Bayer's areas of business include pharmaceuticals; consumer healthcare products, agricultural chemicals, seeds and biotechnology products. The company is a component of the Euro Stoxx 50 stock market index. Bayer was founded in 1863 in Barmen as a partnership between dye salesman Friedrich Bayer and dyer Friedrich Weskott. As was common in this era, the company was established as a dyestuffs producer. The versatility of aniline chemistry led Bayer to expand their business into other areas, and in 1899 Bayer launched the compound acetylsalicylic acid under the trademarked name Aspirin. In 1904 Bayer received a trademark for the "Bayer Cross" logo, which was subsequently stamped onto each aspirin tablet, creating an iconic product that is still sold by Bayer. Other commonly known prod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monsanto
The Monsanto Company () was an American agrochemical and agricultural biotechnology corporation founded in 1901 and headquartered in Creve Coeur, Missouri. Monsanto's best known product is Roundup, a glyphosate-based herbicide, developed in the 1970s. Later the company became a major producer of genetically engineered crops. In 2018, the company ranked 199th on the Fortune 500 of the largest United States corporations by revenue. Monsanto was one of four groups to introduce genes into plants in 1983, and was among the first to conduct field trials of genetically modified crops in 1987. It was one of the top 10 US chemical companies until it divested most of its chemical businesses between 1997 and 2002, through a process of mergers and spin-offs that focused the company on biotechnology. Monsanto was one of the first companies to apply the biotechnology industry business model to agriculture, using techniques developed by biotech drug companies. In this business model, com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toray
is a multinational corporation headquartered in Japan that specializes in industrial products centered on technologies in organic synthetic chemistry, polymer chemistry, and biochemistry. Its founding business areas were fibers and textiles, as well as plastics and chemicals. The company has also diversified into areas such as pharmaceuticals, biotechnology and R&D, medical products, reverse osmosis big membranes, electronics, IT-products, housing and engineering, as well as advanced composite materials. The company is listed on the first section of Tokyo Stock Exchange and is a constituent of the TOPIX 100 and Nikkei 225 stock market indices. History Toray Industries had been originally established as Toyo Rayon in 1926 by Mitsui Bussan, one of the two largest Japanese trading companies (''sogo shosha'') of the time (the other being Mitsubishi Shoji). The fact that Mitsui did not allow the company to be named as a Mitsui company indicates their skepticism of the risk on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teijin Aramid
Teijin Aramid, formerly known as Teijin Twaron, is a company in The Netherlands that produces various high-strength fibers for industrial purposes, most notably their para-aramid, Twaron. Twaron finds applications in numerous markets, such as automotive (tires, hoses, belts), aerospace, civil engineering, construction, leisure goods (e.g. boats), protective clothing (bullet-, fire- and cut-resistant clothing), optical fiber cables, friction and sealing materials and more. The company has been part of the Japanese Teijin Group since 2000, prior to this they were a division of Akzo Nobel, division Industrial Fibers. Next to Twaron, the company markets Technora, Endumax and Teijinconex as well. History Twaron is a heat-resistant and strong synthetic fiber, developed in early 1970s by the Dutch company AKZO, division Enka, later Akzo Nobel Industrial Fibers. The research name of the aramid was originally Fiber X, but soon called Arenka. In 1973 Akzo decided to use sulphuric acid ... [...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 m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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