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Advantages of emulsion polymerization include: [3] High molecular weight polymers can be made at fast polymerization rates. By contrast, in bulk and solution free-radical polymerization, there is a tradeoff between molecular weight and polymerization rate.
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.
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 .
The expression ‘controlled radical polymerization’ is sometimes used to describe a radical polymerization that is conducted in the presence of agents that lead to e.g. atom-transfer radical polymerization (ATRP), nitroxide-(aminoxyl) mediated polymerization (NMP), or reversible-addition-fragmentation chain transfer (RAFT) polymerization.
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.
"The entry of free radicals into latex particles in emulsion polymerization". IA Maxwell, BR Morrison, DH Napper, RG Gilbert, Macromolecules, 24, 1629–40 (1991) (Discovery of the mechanism of an important process in this major industrial process.) Emulsion polymerization: a mechanistic approach. RG Gilbert. London: Academic Press (1995), 362pp
Initiation: Free radicals are generated by initiators such as potassium persulfate (K 2 S 2 O 8) or Azobisisobutyronitrile (AIBN). These radicals are highly reactive and can start the polymerization process by reacting with the monomer units. [11] Propagation: Once the radical reacts with a monomer, it creates a new radical at the end of the ...
Thereby the control agent substantially slows-down the over-all radical polymerisation reaction. However, some CMRP reactions proceed via a different mechanism, called degenerative transfer (DT), [6] which allows controlled radical polymerization reactions to proceed at roughly the same rate as any uncontrolled free radical polymerisation.