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The polymerization of monomers into copolymers is called copolymerization. Copolymers obtained from the copolymerization of two monomer species are sometimes called bipolymers . Those obtained from three and four monomers are called terpolymers and quaterpolymers , respectively. [ 1 ]
It was proposed by Frank R. Mayo and Frederick M. Lewis. [1] The equation considers a monomer mix of two components and and the four different reactions that can take place at the reactive chain end terminating in either monomer ( and ) with their reaction rate constants : The reactivity ratio for each propagating chain end is defined as the ...
Typical monomers are nonpolar ethene and propene. The development of coordination polymerization that enables copolymerization with polar monomers is more recent. [4] Examples of monomers that can be incorporated are methyl vinyl ketones, [5] methyl acrylate, [6] and acrylonitrile. [7] Illustrative metallocene-based coordination catalysts
For the copolymerization of a given pair of monomers, the two experimental reactivity ratios r 1 and r 2 permit the evaluation of (Q 1 /Q 2) and (e 1 – e 2). Values for each monomer can then be assigned relative to a reference monomer, usually chosen as styrene with the arbitrary values Q = 1.0 and e = –0.8. [28]
v. t. e. In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. [1][2][3] There are many forms of polymerization [4] and different systems exist to categorize them.
Composition drift in some degree will occur unless the reactivity ratios for both monomers are equal to 1. In this case, each monomer prefers reaction with itself and the other monomer equally. This causes equal rates of consumption for copolymer formation and leads to random copolymerization. [3]
The ratio of monomer to macromonomer molar concentrations as well as their copolymerization behavior determines the number of chains that are grafted. As the reaction proceeds, the concentrations of monomer to macromonomer change causing random placement of branches and formation of graft copolymers with different number of branches.
In polymer chemistry, anionic addition polymerization is a form of chain-growth polymerization or addition polymerization that involves the polymerization of monomers initiated with anions. The type of reaction has many manifestations, but traditionally vinyl monomers are used. [2][3] Often anionic polymerization involves living polymerizations ...