Catalyst-free, atom-economical and regioselective multicomponent polymerizations of diamines, CS2, and diepoxides toward functional polydithiourethanes

Abstract

Sulfur-containing polymers have attracted extensive attention due to their fascinating properties and promising applications; thus, it is significant to develop economical and efficient synthesis strategies, extend the polymer family, and establish various applications for sulfur-containing polymers. In this work, the first example of room temperature one-step conversion from CS₂ to hydroxyl-functional polydithiourethanes is demonstrated through a multicomponent polymerization of diamines, CS₂, and diepoxides. This multicomponent polymerization enjoys the unique advantages of atom economy, catalyst-free and room temperature conditions, and abundant and cheap monomers. A series of hydroxyl-functional polydithiourethanes were produced with high molecular weights of up to 53 100 g mol⁻¹ and high yields of up to 97%. Nonconventional fluorescence was observed from the polydithiourethanes, owing to the “heterodox clusters” composed of lone-pair-containing electron-rich heteroatoms. Thanks to the strong coordination of dithiourethane moieties with metal ions, these polymers can be utilized to sequester toxic Hg²⁺ ions with high removal efficiency (>99.9%). This multicomponent polymerization can make use of abundantly existing diamines, CS₂, and diepoxides to produce functional polydithiourethanes with diverse structures, demonstrating its great potential in practical applications.