Controlled Radical <i>Ab Initio</i> Emulsion Polymerization of <i>n</i>‐Butyl Acrylate by Reverse Iodine Transfer Polymerization (RITP): Effect of the Hydrolytic Disproportionation of Iodine

Abstract

Abstract Summary: Controlled radical polymerization of n ‐butyl acrylate by reverse iodine transfer polymerization (RITP) was achieved in ab initio emulsion polymerization to yield a stable and uncolored latex (particle diameter d p = 106 nm). Hydrolysis of iodine, I 2 , was responsible for an upward deviation from the targeted molecular weight $\overline M _{{\rm n},{\rm targeted}}$ = 10 400 g · mol −1 . The iodide concentration [I − ] was followed by an iodide selective electrode and the amount of efficient iodine (33%) was successfully correlated with the experimental molecular weight $\overline M _{{\rm n},{\rm exp}}$ = 31 000 g · mol −1 . Finally, a simplified mechanism of RITP in ab initio emulsion polymerization taking into account the iodine hydrolysis was proposed. Evolution of molecular weight and polydispersity index in RITP of BuA in ab initio emulsion. magnified image Evolution of molecular weight and polydispersity index in RITP of BuA in ab initio emulsion.