Cationic bottlebrush brush polymers via sequential SI‐ROMP and SI‐ARGET‐ATRP

Abstract Here we describe a facile approach to preparing cationic bottlebrush brush polymers via sequential surface‐initiated (SI) ring‐opening metathesis polymerization and SI activators regenerated by electron transfer atom transfer radical polymerization. These techniques afforded both bottlebrush polymer brushes and their linear polymer brush analogues with cationic triphenylphosphonium pendant groups. Utilization of two controlled polymerization techniques with orthogonal requirements for monomers and additives allowed the polymerization of the backbone and the pendant side chains to be controlled independently. Grafting polymer side chains to a polymer brush backbone resulted in a thickness increase of ca 70%, indicating that the polymers are forced into a stretched conformation with greater surface coverage than was afforded by the linear brush polymers. As a result of the stretched conformation, greater ionic conductivity in the bottlebrush brush architectures was observed. © 2022 Society of Industrial Chemistry.