what is acrylic...?
give correct answer please..
Answers
Answer:
Acrylic : Acrylic is a strong, lightweight and warm synthetic fibre that resembles wool. It is available in a number of colours and is more durable and affordable than natural wool.
hope help u....
Answer:
HEYA MATE HERE IS YOUR ANSWER.
Explanation:
Acrylic fibers are synthetic fibers made from a polymer (polyacrylonitrile) with an average molecular weight of -100,000, about 1900 monomer units. For a fiber to be called "acrylic" in the US, the polymer must contain at least 85% acrylonitrile monomer. Typical comonomers are vinyl acetate or methyl acrylate. DuPont created the first acrylic fibers in 1941 and trademarked them under the name Orlon. It was first developed in the mid-1940s but was not produced in large quantities until the 1950s. Strong and warm, acrylic fiber is often used for sweaters and tracksuits and as linings for boots and gloves, as well as in furnishing fabrics and carpets. It is manufactured as a filament, then cut into short staple lengths similar to wool hairs, and spun into yarn.
Modacrylic is a modified acrylic fiber that contains at least 35% and at most 85% acrylonitrile monomer. The comonomers vinyl chloride, vinylidene chloride or vinyl bromide used in modacrylic give the fiber flame retardant properties. End-uses of modacrylic include faux fur, wigs, hair extensions and protective clothing.
polymer is formed by free-radical polymerization in aqueous suspension. The fiber is produced by dissolving the polymer in a solvent such as N,N-dimethylformamide (DMF) or aqueous sodium thiocyanate, metering it through a multi-hole spinnerette and coagulating the resultant filaments in an aqueous solution of the same solvent (wet spinning) or evaporating the solvent in a stream of heated inert gas (dry spinning). Washing, stretching, drying and crimping complete the processing. Acrylic fibers are produced in a range of deniers, usually from 0.9 to 15, as cut staple or as a 500,000 to 1 million filament tow. End uses include sweaters, hats, hand-knitting yarns, socks, rugs, awnings, boat covers, and upholstery; the fiber is also used as "PAN" precursor for carbon fiber. Production of acrylic fibers is centered in the Far East, Turkey, India, Mexico, and South America, though a number of European producers still continue to operate, including Dralon and Fisipe. US producers have ended production (except for specialty uses such as in friction materials, gaskets, specialty papers, conductive, and stucco), though acrylic tow and staple are still spun into yarns in the USA. Former U.S. brands of acrylic included Acrilan (Monsanto), and Creslan (American Cyanamid). Other brand names that are still in use include Dralon (Dralon GmbH) and Drytex (Sudamericana de Fibras, S.A.).[citation needed] In the late 1950s Courtaulds Ltd began investigating the production of an acrylic fibre later to be called "courtelle" by a process of solvent polymerisation. Methyl acrylate (6%) and acrylonitrile were polymerised in a 50% solution of sodium thiocyanate to produce a dope ready for spinning into a waterbath to produce "courtelle" fibre in various grades of denier. The sodium thiocyanate solution was reconcentrated and re used. The reaction was a continuous process with about 5% of reactants being recycled. This recycling process resulted in the build up of pollutants in the process as did the recycling of the solvent. A great deal of research in the Chemical engineering laboratory in Lockhurst Lane, Coventry, and on the pre production pilot plant at Little Heath overcame the recycling problems and resulted in the process becoming a commercial success at a new production plant in Grimsby.
HOPE THIS HELPS YOU
MARK ME AS BRAINLISTER