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Polystyrene (PS) / ˌ p ɒ l i ˈ s t aɪ r iː n / is a synthetic polymer made from monomers of the aromatic hydrocarbon styrene. [5] Polystyrene can be solid or foamed. General-purpose polystyrene is clear, hard, and brittle. It is an inexpensive resin per unit weight. It is a poor barrier to air and water vapor and has a relatively low ...
Styrene is an organic compound with the chemical formula C 6 H 5 CH=CH 2.Its structure consists of a vinyl group as substituent on benzene.Styrene is a colorless, oily liquid, although aged samples can appear yellowish.
Formation of polystyrene, a polymer with an organic backbone. Common synthetic polymers have main chains composed of carbon, i.e. C-C-C-C.... Examples include polyolefins such as polyethylene ((CH 2 CH 2 ) n ) and many substituted derivative ((CH 2 CH(R)) n ) such as polystyrene (R = C 6 H 5 ), polypropylene (R = CH 3 ), and acrylates (R = CO 2 ...
More than 330 million tons of these polymers are made every year (2015). [16] Most commonly, the continuously linked backbone of a polymer used for the preparation of plastics consists mainly of carbon atoms. A simple example is polyethylene ('polythene' in British English), whose repeat unit or monomer is ethylene.
When this curl breaks, it leaves small chains sprouting from the main carbon backbone. Branched carbon chains cannot line up as close to each other as unbranched chains can. This causes less contact between atoms of different chains, and fewer opportunities for induced or permanent dipoles to occur. A low density results from the chains being ...
Other monomer units, such as formaldehyde hydrates or simple aldehydes, are able to polymerize themselves at quite low temperatures (ca. −80 °C) to form trimers; [3] molecules consisting of 3 monomer units, which can cyclize to form ring cyclic structures, or undergo further reactions to form tetramers, [3] or 4 monomer-unit compounds.
Ethylbenzene is an organic compound with the formula C 6 H 5 CH 2 CH 3.It is a highly flammable, colorless liquid with an odor similar to that of gasoline.This monocyclic aromatic hydrocarbon is important in the petrochemical industry as a reaction intermediate in the production of styrene, the precursor to polystyrene, a common plastic material.
Polymers are composed of long molecular chains which form irregular, entangled coils in the melt. Some polymers retain such a disordered structure upon freezing and readily convert into amorphous solids. In other polymers, the chains rearrange upon freezing and form partly ordered regions with a typical size of the order 1 micrometer. [3]