Atom transfer radical polymerization chain length dependence

Transfer to solvent. A significant decrease in polymer chain length is often found when polymerizations are carried out in solution rather than in the undiluted state, and this variation is a function of both the extent of dilution and the type of solvrait used. The effectiveness of a solvent in a transfer reaction depends largely on the amount present, the strength of the bond involved in the abstraction step, and the stability of the solvent radical formed. With the exception of llnorine, halogen atoms are easily transferred, and the reaction of styrene in CCI4 is a good example of this chain transfer. 

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