Diversely Substituted Polyamide Structures through Thiol Ene Polymerization of Renewable Thiolactone Building Blocks

A thiolactone derivative of 10-undecenoic acid was used as a renewable AB' monomer for the one-pot synthesis of diversely substituted polyamide structures, containing amide moieties both in the polymer backbones and in their side chains. Nucleophilic aminolysis of the thiolactone entity liberates a thiol, which further reacts in a stepwise thiol-ene photopolymerization reaction. Using different primary amines, several structurally diverse polyamides, with physical properties dependent on the length and chemical identity of the side chain, were obtained. Postpolymerization oxidation of the sulfide linkages in the polymer backbone to their corresponding sulfoxides and sulfones altered the material, with the degree of oxidation having an impact on the final mechanical properties. Furthermore, this mild and straightforward polymerization procedure was applied for the synthesis of functional polymer networks.