Elemental sulfur utilization: Construction of a reprocessable covalent crosslinked polydisulfide with enhanced mechanical properties

Abstract

Herein, a polydisulfide with uniformly distributed aldehyde groups was prepared through the terpolymerization of an aldehyde-containing episulfide, 2-(phenoxymethyl)thiirane, and elemental sulfur. A thermoset polydisulfide with a crosslinking network was constructed by leveraging the Schiff base reaction between amines and aldehyde groups. Compared to the linear polymers, the crosslinked polydisulfide exhibited a 2–10 °C increase in its glass transition temperature. In addition, the covalent crosslinking network enhanced the mechanical properties of the polydisulfide compared to those of the original linear polymer, and the mechanical properties could be modulated by adjusting the crosslinking density of the polymer. Moreover, the polymer exhibited processability and shape-memory properties when heated to a specific temperature.