Reactivities of alkyl methacrylates in their radical polymerization

Abstract

Abstract The effect of the alkyl group on radical polymerizations of alkyl methacrylates (RMA) has been investigated. From the results on copolymerizations of RMA(M 2 ) with styrene or B ‐chloroethyl methacrylate (M 1 ), the relative reactivities (l r 1 ) of RMA toward attack of polymer radicals were plotted by the Taft's equation: log (1/ r 1 ) = ρ * σ * +δ E 8 . The plot could correlate with polar substituent constants (σ * ), but not steric substituent constants (E 8 ) of the alkyl substituents in RMA. These results might strongly indicate that the radical reactivities of RMA depended on the polar character of the alkyl groups, but not on their steric character. This conclusion is compared with other experimental results and discussed.