Use of Methyl 2-(Bromomethyl)acrylate as a Chain-Transfer Agent To Yield Functionalized Macromonomers via Conventional and Living Radical Polymerizations
journal contributionposted on 21.07.2000, 00:00 by Stefan A. F. Bon, Stuart R. Morsley, Carl Waterson, David M. Haddleton
The chain-transfer constants of methyl (2-bromomethyl)acrylate (MBrMA) in bulk polymerizations of methyl methacrylate (MMA) and styrene were determined at 70 °C using both the Mayo method (1/DPn as well as 2/DPw) and the chain-length-distribution procedure (Λ). The CMBrMA values using 2/DPw and Λ were consistent, i.e., 1.28 and 1.20 for MMA and 11.44 and 10.92 for styrene, respectively. MBrMA was used as a chain-transfer agent in the emulsion polymerization of MMA to yield an α-bromo-functionalized macromonomeric latex (〈Mn〉 = 9.6 × 103 g mol-1; PDI = 1.80), which was subsequently copolymerized with styrene to yield the corresponding poly(styrene-graft-MMA) copolymer. MBrMA was used as an addition−fragmentation agent in the living radical polymerization of MMA mediated by copper(I) bromide/N-(n-octyl)-2-pyridylmethanimine. In situ addition of a 5-fold equivalent of MBrMA and Cu(0) to this polymerization quenched the reaction and transformed the ω-bromide into the methacrylate-based macromonomer quantitatively.