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Many are produced using radical initiators which are produced from organic peroxides. Still others (polystyrene) are produced using anionic initiators such as butyl lithium. An exception from the usual rules, polyvinyl alcohol, (CH 2 CHOH) n, is produced by hydrolysis of polyvinyl acetate. Vinyl alcohol is not sufficiently stable to undergo ...
Styrene monomer (SM) is an intermediate product. It is a colorless liquid that polymerizes easily. Polystyrene (PS) is a thermoplastic resin that is used in many applications, such as disposable packaging, electronic devices, large appliances (for example in refrigeration liners) and household goods.
Acrylonitrile butadiene styrene (ABS) (chemical formula (C 8 H 8) x · (C 4 H 6) y · (C 3 H 3 N) z) is a common thermoplastic polymer. Its glass transition temperature is approximately 105 °C (221 °F). [4] ABS is amorphous and therefore has no true melting point. ABS is a terpolymer made by polymerizing styrene and acrylonitrile in the ...
If styrene-butane co-polymer has a high butylene content, styrene-butadiene rubber (SBR) is formed. The impact strength of styrene-butadiene co-polymers is based on phase separation, polystyrene and poly-butane are not soluble in each other (see Flory–Huggins solution theory). Co-polymerization creates a boundary layer without complete mixing.
About 50% of car tires are made from various types of SBR. The styrene/butadiene ratio influences the properties of the polymer: with high styrene content, the rubbers are harder and less rubbery. [3] SBR is not to be confused with the thermoplastic elastomer, styrene-butadiene block copolymer, although being derived from the same monomers.
Styrene, for example, is distilled at temperatures above 100 °C whereupon it undergoes thermal polymerisation at a rate of ~2% per hour. [1] This polymerisation is undesirable, as it can foul the fractionating tower ; it is also typically exothermic , which can lead to a runaway reaction and potential explosion if left unchecked.
Styrene maleic anhydride (SMA or SMAnh) is a synthetic polymer that is built-up of styrene and maleic anhydride monomers. In one copolymer , the monomers can be almost perfectly alternating. [ 1 ] but (random) copolymerisation with less than 50% maleic anhydride content is also possible. [ 2 ]
ASA can be made by either a reaction process of all three monomers (styrene, acrylonitrile, acrylic ester) or a graft process, although the graft process is the typical method. A grafted acrylic ester elastomer is introduced during the copolymerization of styrene and acrylonitrile. The elastomer is introduced as a powder. [11]