Nitroxide‐Mediated Polymerization of an Organo‐Soluble Protected Styrene Sulfonate: Development of Homo‐ and Random Copolymers

Trioctylammonium p ‐styrenesulfonate (SS‐TOA), is polymerized using the BlocBuilder unimolecular initiator and SG1. Polymerizations are controlled for low theoretical molecular weight, resulting in low polydispersities and a linear increase in $\overline {M} _{{\rm n}} $ up to ≈35% conversion. The product of the propagation rate constant and the equilibrium constant for SS‐TOA is 1.4–2 times that of styrene at the same temperature, suggesting its suitability as a controlling co‐monomer for BlocBuilder‐mediated NMP with methacrylates. SS‐TOA is effective as a controlling co‐monomer for gradient polymerization with GMA using NHS‐modified BlocBuilder. The resulting copolymer has a narrow, monomodal MWD and a linear increase in $\overline {M} _{{\rm n}} $ with conversion, suggesting SS‐TOA is an effective NMP co‐monomer.