Design of AB divinyl “template monomers” toward alternating sequence control in metal-catalyzed living radical polymerization

Abstract

For alternating repeat-unit sequence via living radical polymerization, “template monomers” were designed and polymerized, where two polymerizable alkene (vinyl) functions [e.g., methacrylate (M) and acrylate (A)] were placed side by side at the 1,8-positions on a rigid naphthalene scaffold. Even for such a divinyl monomer, highly selective intramolecular radical propagation was achieved with metal-catalyzed living radical polymerization systems, to give linear controlled polymers without cross-linking. The naphthalene template was cleaved viahydrolysis from the resultant polymer, and subsequently methylated for sequence characterization. ¹H NMR analysis demonstrated that the polymers consisted of highly alternating sequences (A-M-A: >80%), practically free from homo triad sequences (M-M-M).