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In polymer chemistry, radical polymerization (RP) is a method of polymerization by which a polymer forms by the successive addition of a radical to building blocks (repeat units). Radicals can be formed by a number of different mechanisms, usually involving separate initiator molecules .
In polymer chemistry, polymerisation inhibitors (US: polymerization inhibitors) are chemical compounds added to monomers to prevent their self-polymerisation. Unsaturated monomers such as acrylates , vinyl chloride , butadiene and styrene require inhibitors for both processing and safe transport and storage.
It is produced by polymerization of styrene in the presence of polybutadiene dissolved (in styrene). Polymerization takes place simultaneously in two ways: [64] Graft copolymerization: The growing polystyrene chain reacts with a double bond of the polybutadiene. As a result, several polystyrene chains are attached to one polybutadiene.
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. The compound evaporates easily and has a sweet smell, although high concentrations have a less pleasant odor.
1,1-Diphenylethylene mediates the radical polymerization of methyl acrylate or styrene. Mediation by 1,1-Diphenylethylene generates low molecular weight polymer by a termination reaction. [ 3 ] Additionally, because 1,1-Diphenylethylene has a lower pKa than styrene, it is an effective mediator in the anionic living polymerization of styrene ...
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 ]
In chain-growth (or chain) polymerization, the only chain-extension reaction step is the addition of a monomer to a growing chain with an active center such as a free radical, cation, or anion. Once the growth of a chain is initiated by formation of an active center, chain propagation is usually rapid by addition of a sequence of monomers.
Living free radical polymerization is a type of living polymerization where the active polymer chain end is a free radical. Several methods exist. Several methods exist. IUPAC recommends [ 1 ] to use the term " reversible-deactivation radical polymerization " instead of "living free radical polymerization", though the two terms are not synonymous.