Unsaturated sulfur-containing polymers from modular alcohol click chemistry

Abstract

The traditional polymerization methods utilizing thiol–yne Michael addition have made significant progress in the past decades, despite suffering from the poor availability of dithiols. Here, a modular and efficient click reaction for connecting primary and secondary alcohols with activated alkynes via carbonyl sulfide (COS) was developed. The click reaction is successfully applied to synthesize different kinds of polythiocarbonates by the step-wise polyaddition of diols, dipropiolates, and COS. Diols are a diverse and abundant class of compounds that can be obtained from biomass and COS is released as industrial waste, while dipropiolates can be obtained through a one-step condensation reaction of diols with propiolic acid. In addition to the ease of obtaining the monomers, this method is atom-economical, metal-free, and involves mild conditions. Overall, the polymers have broad prospects for green materials given their facile synthesis, readily available feedstocks, desirable performance.