There are three kinds of man-made fibers: those made by “transformation of natural polymers” (also called regenerated cellulosics), those made from synthetic polymers and those made from inorganic materials (These include the fibers made of glass, metal, ceramics and carbon.) But by far the largest group of man made synthetic fibers being produced today are made from synthetic polymers.
Man made fibers from synthetic polymers are created using polymerization of various chemical inputs to create polymers. Polymerization is the process of combining many small molecules into a large molecule – a polymer. Polymers are simply large molecules composed of repeating structural units. Polymers used for synthetic fibers are produced from intermediates (which in turn have been produced from crude oil) and applying a catalyst. Key intermediates are p-Xylene, teraphtalic acid, ethylene glycol and acrylonitrile; catalysts – manganese, cobalt and antimony oxide – are used to control the processes.Synthetic polymers include vulcanized rubber, Bakelite and neoprene (and many more) in addition to polymers used in fibers: polyester, nylon, polystyrene, polyethylene, PVC, and polyacrylonitrile (known as acrylic).
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