They called the product "meta styrol" analysis showed that it was chemically identical to Simon's Styroloxyd. By 1845 Jamaican-born chemist John Buddle Blyth and German chemist August Wilhelm von Hofmann showed that the same transformation of styrol took place in the absence of oxygen. Several days later, Simon found that the styrol had thickened into a jelly he dubbed styrol oxide ("Styroloxyd") because he presumed an oxidation. From storax, the resin of the Oriental sweetgum tree Liquidambar orientalis, he distilled an oily substance, a monomer that he named styrol. Polystyrene was discovered in 1839 by Eduard Simon, an apothecary from Berlin. 5.1.1 Impact-resistant polystyrene (PS-I).4.2.4 Water absorption of polystyrene foams.It is accumulating as a form of litter in the outside environment, particularly along shores and waterways, especially in its foam form, and in the Pacific Ocean.
Under ASTM standards, polystyrene is regarded as not biodegradable. This temperature behaviour is exploited for extrusion (as in Styrofoam) and also for molding and vacuum forming, since it can be cast into molds with fine detail. Īs a thermoplastic polymer, polystyrene is in a solid (glassy) state at room temperature but flows if heated above about 100 ☌, its glass transition temperature. Uses include protective packaging (such as packing peanuts and in the jewel cases used for storage of optical discs such as CDs and occasionally DVDs), containers, lids, bottles, trays, tumblers, disposable cutlery, in the making of models, and as an alternative material for phonograph records. Polystyrene can be naturally transparent, but can be coloured with colourants.
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Polystyrene is one of the most widely used plastics, the scale of its production being several million tonnes per year. It is a poor barrier to oxygen and water vapour and has a relatively low melting point. It is an inexpensive resin per unit weight. General-purpose polystyrene is clear, hard, and brittle. Polystyrene ( PS) / ˌ p ɒ l i ˈ s t aɪ r iː n/ is a synthetic aromatic hydrocarbon polymer made from the monomer known as styrene. Bottom of a vacuum-formed cup fine details such as the glass and fork food contact materials symbol and the resin identification code symbol are easily molded
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