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Polystyrene is commonly injection molded, vacuum formed, or extruded, while expanded polystyrene is either extruded or molded in a special process. Polystyrene copolymers are also produced; these contain one or more other monomers in addition to styrene.
The product is polystyrene. As alkenes can polymerize in somewhat straightforward radical reactions, they form useful compounds such as polyethylene and polyvinyl chloride (PVC), [3] which are produced in high tonnages each year [3] due to their usefulness in manufacturing processes of commercial products, such as piping, insulation and packaging.
The composition and structural type of the copolymer depend on these reactivity ratios r 1 and r 2 according to the Mayo–Lewis equation, also called the copolymerization equation or copolymer equation, [7] [6] for the relative instantaneous rates of incorporation of the two 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] The polymer is formed by a radical polymerization, using an organic peroxide as the initiator. The main characteristics of SMA copolymer are its transparent appearance, high heat ...
Free radical polymerization has found applications including the manufacture of polystyrene, thermoplastic block copolymer elastomers, [29] cardiovascular stents, [30] chemical surfactants [31] and lubricants. Block copolymers are used for a wide variety of applications including adhesives, footwear and toys.
The easiest way to visualize the mechanism of a step-growth polymerization is a group of people reaching out to hold their hands to form a human chain—each person has two hands (= reactive sites). There also is the possibility to have more than two reactive sites on a monomer: In this case branched polymers production take place.
The use of the term polymer alloy for a polymer blend is discouraged, as the former term includes multiphase copolymers but excludes incompatible polymer blends. [3] Examples of miscible polymer blends: homopolymer–homopolymer: polyphenylene oxide (PPO) – polystyrene (PS): noryl developed by General Electric Plastics in 1966 (now owned by ...
It is one of the most developed methods in chain-growth polymerization. Currently, most polymers in our daily life are synthesized by free radical polymerization, including polyethylene, polystyrene, polyvinyl chloride, polymethyl methacrylate, polyacrylonitrile, polyvinyl acetate, styrene butadiene rubber, nitrile rubber, neoprene, etc.