Polyvinyl pyrrolidone mediated exfoliation of transition metal dichalcogenides: Comparative evaluation of exfoliated MoS₂ and WS₂ in epoxy toughening

2D materials are considered as an effective choice for the toughening of epoxy composites and enhancing their mechanical properties. Among the 2D materials, transition metal dichalcogenides, especially MoS2 and WS2, are getting wider attention due to their behavior analogous to graphene. The restacking and agglomeration tendency of TMDs due to weak Vander Waal's forces limits their application in epoxy toughening. To overcome the agglomeration issues, we are proposing a new approach for TMD exfoliation using Polyvinyl pyrrolidone (PVP); followed by its incorporation into the epoxy matrix. The exfoliation of TMDs using PVP is characterized by various techniques like FTIR, Raman spectroscopy, XRD analysis, and so forth. The enhanced mechanical properties of PVP exfoliated MoS2 and WS2 at a very low loading of 0.1 wt% are remarkable. The highly exfoliated WS2 showcases higher toughness than MoS2, with a 614% improvement in toughness and 43.5% improvement in tensile strength, respectively. The improvement in mechanical properties of these nanocomposites can be attributed to the good dispersion of PVP-exfoliated TMDs in the epoxy matrix. Highlights Highlights the role of Polyvinyl pyrrolidone in exfoliating TMDs. The exfoliation efficiency of PVP is compared for MoS2 and WS2. The utilization of PVP exfoliated MoS2 and WS2 in epoxy toughening is portrayed. The effectiveness of epoxy composites in aerospace and coating applications is revealed.