Bio-Sourced 4-Aryl-1,2-Dithiolanes for Recyclable Poly(disulfide)s with High Performance.

The development of recyclable polymers presents a solution to the urgent issues of circular plastics economy. To this end, there is an increasing interest in expanding the utility of poly(disulfide)s, which contains dynamic covalent S─S bonds to enable intrinsic degradability. Lipoic acid and its derivatives represent the most widely used class of monomers for the preparation of poly(disulfide)s. However, their physical properties are usually on the soft side of thermoplastics and can face challenges in wider applications. In this contribution, we report a scalable synthesis of a new class of aryl-substituted 1,2-dithiolane monomers from bio-sourced phenol ethers and their ring-opening polymerization to aryl-substituted poly(disulfide)s. The aryl-substituted poly(disulfide)s display high recyclability without the cost of stability. The introduction of aryl side chains systematically improves the thermal properties of poly(disulfide)s. The optical properties of aryl-substituted poly(disulfide)s are competitive and so are the mechanical properties of the crosslinked network, showing potential for applications in sustainable materials.