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Dry Jet-wet Spinning
Spinning is a manufacturing process for creating polymer fibers. It is a specialized form of extrusion that uses a spinneret to form multiple continuous filaments.. Melt spinning If the polymer is a thermoplastic then it can undergo melt spinning. The molten polymer is extruded through a spinneret composed of capillaries where the resulting filament is solidified by cooling. Nylon, olefin, polyester, saran, and sulfar are produced via this process. Extrusion spinning Pellets or granules of the solid polymer are fed into an extruder. The pellets are compressed, heated and melted by an extrusion screw, then fed to a spinning pump and into the spinneret. Direct spinning The direct spinning process avoids the stage of solid polymer pellets. The polymer melt is produced from the raw materials, and then from the polymer finisher directly pumped to the spinning mill. Direct spinning is mainly applied during production of polyester fibers and filaments and is dedicated to high producti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymer
A polymer () is a chemical substance, substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeat unit, repeating subunits derived from one or more species of monomers. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compound (chemistry), compounds, produces unique physical property, physical properties including toughness, high rubber elasticity, elasticity, viscoelasticity, and a tendency to form Amorphous solid, amorphous and crystallization of polymers, semicrystalline structures rath ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precipitate
In an aqueous solution, precipitation is the "sedimentation of a solid material (a precipitate) from a liquid solution". The solid formed is called the precipitate. In case of an inorganic chemical reaction leading to precipitation, the chemical reagent causing the solid to form is called the precipitant. The clear liquid remaining above the precipitated or the centrifuged solid phase is also called the supernate or supernatant. The notion of precipitation can also be extended to other domains of chemistry (organic chemistry and biochemistry) and even be applied to the solid phases (e.g. metallurgy and alloys) when solid impurities segregate from a solid phase. Supersaturation The precipitation of a compound may occur when its concentration exceeds its solubility. This can be due to temperature changes, solvent evaporation, or by mixing solvents. Precipitation occurs more rapidly from a strongly supersaturated solution. The formation of a precipitate can be caused by a ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microfiber
Microfiber (microfibre in British English) is synthetic fibre finer than one Denier (unit), denier or decitex/thread, having a diameter of less than ten micrometre, micrometers. The most common types of microfiber are made variously of polyesters; polyamides (e.g., nylon, Kevlar, Nomex); and combinations of polyester, polyamide, and polypropylene. Microfiber is used to make mats, knits, and weaves, for apparel, upholstery, industrial filters, and cleaning products. The shape, size, and combinations of synthetic fibers are chosen for specific characteristics, including softness, toughness, absorption, water repellence, electrostatics, and filtering ability. They are commonly used for cleaning scratch prone surfaces such as Display device, displays, glass, and Lens, lenses. Microfiber cloth makes use of van der Waals force to remove dirt without scratches. History Production of ultra-fine fibers (finer than 0.7 Denier (unit), denier) dates to the late 1950s, using melt-blown s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyacrylonitrile
Polyacrylonitrile (PAN) is a synthetic, semicrystalline organic polymer resin, with the linear formula (CH2CHCN)n. Almost all PAN resins are copolymers with acrylonitrile as the main monomer. PAN is used to produce large variety of products including ultra filtration membranes, hollow fibers for reverse osmosis, fibers for textiles, and oxidized PAN fibers. PAN fibers are the chemical precursor of very high-quality carbon fiber. PAN is first thermally oxidized in air at 230 °C to form an oxidized PAN fiber and then carbonized above 1000 °C in inert atmosphere to make carbon fibers found in a variety of both high-tech and common daily applications such as civil and military aircraft primary and secondary structures, missiles, solid propellant rocket motors, pressure vessels, fishing rods, tennis rackets and bicycle frames. It is a component repeat unit in several important copolymers, such as styrene-acrylonitrile (SAN) and acrylonitrile butadiene styrene (ABS) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyethylene
Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging (plastic bags, plastic films, geomembranes and containers including bottles, cups, jars, etc.). , over 100 million tonnes of polyethylene resins are being produced annually, accounting for 34% of the total plastics market. Many kinds of polyethylene are known, with most having the chemical formula (C2H4)''n''. PE is usually a mixture of similar polymers of ethylene, with various values of ''n''. It can be ''low-density'' or ''high-density'' and many variations thereof. Its properties can be modified further by crosslinking or copolymerization. All forms are nontoxic as well as chemically resilient, contributing to polyethylene's popularity as a multi-use plastic. However, polyethylene's chemical resilience also makes it a long-lived and decomposition-resistant pollutant when disposed of improperly. Being a h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultra-high-molecular-weight Polyethylene
Ultra-high-molecular-weight polyethylene (UHMWPE, UHMW) is a subset of the thermoplastic polyethylene. Also known as high-modulus polyethylene (HMPE), it has extremely long chains, with a molecular mass typically between 2 and 6 million amu. The longer chain serves to transfer load more effectively to the polymer backbone by strengthening intermolecular interactions. This results in a very tough material, with the highest impact strength of any thermoplastic presently made. UHMWPE is odorless, tasteless, and nontoxic. It embodies all the characteristics of high-density polyethylene (HDPE) with the added traits of being resistant to concentrated acids and alkalis, as well as numerous organic solvents. It is highly resistant to corrosive chemicals except oxidizing acids; has extremely low moisture absorption and a very low coefficient of friction; is self-lubricating (see boundary lubrication); and is highly resistant to abrasion, in some forms being 15 times more resistant to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gelatin Dessert
Gelatin desserts are desserts made with a sweetened and flavoured processed collagen product (gelatin), which makes the dessert "set" from a liquid to a soft elastic solid gel. This kind of dessert was first recorded as "jelly" by Hannah Glasse in her 18th-century book ''The Art of Cookery'', appearing in a layer of trifle. Jelly recipes are included in the 19th-century cookbooks of English food writers Eliza Acton and Mrs Beeton. Jelly can be made by combining plain gelatin with other ingredients or by using a premixed blend of gelatin with additives. Fully prepared gelatin desserts are sold in a variety of forms, ranging from large decorative shapes to individual serving cups. Popular brands of premixed gelatin include Aeroplane Jelly in Australia, Hartley's (formerly Rowntree's) in the United Kingdom, and Jell-O from Kraft Foods and Royal from Jel Sert in North America. In the United States and Canada, this dessert is known by the genericized trademark "jello". History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gelation
In polymer chemistry, gelation (gel transition) is the formation of a gel from a system with polymers. Branched polymers can form links between the chains, which lead to progressively larger polymers. As the linking continues, larger branched polymers are obtained and at a certain extent of the reaction, links between the polymer result in the formation of a single macroscopic molecule. At that point in the reaction, which is defined as gel point, the system loses fluidity and viscosity becomes very large. The onset of gelation, or gel point, is accompanied by a sudden increase in viscosity. This "infinite" sized polymer is called the gel or network, which does not dissolve in the solvent, but can swell in it. Background Gelation is promoted by gelling agents. Gelation can occur either by physical linking or by chemical crosslinking. While the physical gels involve physical bonds, chemical gelation involves covalent bonds. The first quantitative theories of chemical gelati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellulose
Cellulose is an organic compound with the chemical formula, formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of glycosidic bond, β(1→4) linked glucose, D-glucose units. Cellulose is an important structural component of the primary cell wall of green plants, many forms of algae and the oomycetes. Some species of bacteria secrete it to form biofilms. Cellulose is the most abundant biopolymer, organic polymer on Earth. The cellulose content of cotton fibre is 90%, that of wood is 40–50%, and that of dried hemp is approximately 57%. Cellulose is mainly used to produce paperboard and paper. Smaller quantities are converted into a wide variety of derivative products such as cellophane and rayon. Conversion of cellulose from energy crops into biofuels such as cellulosic ethanol is under development as a renewable fuel source. Cellulose for industrial use is mainly obtained from wood pulp and cotton. Cellulose is also greatly affected by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyocell
Lyocell is a semi-synthetic fibre used to make textiles for clothing and other purposes. It is a form of regenerated cellulose made by dissolving pulp and dry jet-wet spinning. Unlike rayon, which is made by the more common viscose processes, Lyocell production does not use carbon disulfide, which is toxic to workers and the environment. Lyocell was originally trademarked as Tencel in 1982. "Lyocell" has become a genericised trademark used to refer to the Lyocell process for making cellulose fibres. The U.S. Federal Trade Commission defines Lyocell as "a fiber composed of cellulose precipitated from an organic solution in which no substitution of the hydroxy groups takes place, and no chemical intermediates are formed". It classifies the fibre as a sub-category of rayon. Names Other trademarked names for Lyocell fibres are Tencel ( Lenzing AG), Newcell (Akzo Nobel), and Seacell (Zimmer AG). The Aditya Birla Group also sells it under the brand name Excel. There are other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spandex
Spandex, Lycra, or elastane is a synthetic fiber known for its exceptional elasticity. It is a polyether- polyurea copolymer that was invented in 1958 by chemist Joseph Shivers at DuPont. Name The name ''spandex'', which is an anagram of the word "expands", is the preferred name in North America. In continental Europe, it is referred to by variants of ''elastane''. It is primarily known as ''Lycra'' in the UK, Ireland, Portugal, Spain, Latin America, Australia, and New Zealand. Brand names for spandex include Lycra (made by The Lycra Company, previously a division of DuPont Textiles and Interiors), Elaspan (The Lycra Company), Acepora ( Taekwang Group), Creora (Hyosung), INVIYA ( Indorama Corporation), ROICA and Dorlastan (Asahi Kasei), Linel (Fillattice), and ESPA ( Toyobo). Production Unlike many other synthetic fibers, spandex cannot be melt-processed because the polymer degrades upon melting. Spandex fibers are produced by several spinning technologies. Typically ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modacrylic
A modacrylic is a synthetic copolymer. Modacrylics are soft, strong, resilient and dimensionally stable. They can be easily dyed, show good press and shape retention, and are quick to dry. They have outstanding resistance to chemicals and solvents, are not attacked by moths or mildew, and are nonallergenic. Among their uses are in apparel linings, furlike outerwear, paint-roller covers, scatter rugs, carpets, and work clothing and as hair in wigs.''Modacrylic.'' Columbia Encyclopedia. 20 June 2006. http://www.bartleby.com/65/mo/modacryl.html Commercial production of modacrylic fiber began in 1949 by Union Carbide Corporation in the United States. Modacrylic and acrylic fibers are similar in composition and at one time were in the same category. In 1960 the Federal Trade Commission decided to separate the two fibers and establish a category for each. The Federal Trade Commission defines modacrylic fibers as manufactured fibers in which the fiber-forming substance is any long-cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
