Study of Structural and Multifunctional Characteristics in Dynamic Transesterification-Aided Epoxy Carbon Nanocomposites

Abstract

Vitrimeric nanocomposites (VNCs) are futuristic materials exhibiting multifunctional properties with sustainable capabilities. However, achieving filler-derived functionalities harmoniously with their dynamic characteristics is highly momentous in VNCs. Herein, the vitrimeric thiol-epoxy matrix incorporating tyre-waste-derived carbon nanosheets (CNS) is shown as a versatile nanocomposite integrating flexibility, high strength, and tunable electrical conductivity, together with self-healing and shape-memory characteristics. The transesterification-aided bond exchange reactions enabled vitrimeric features, while the CNS endorsed electrical transport, mechanical, thermal, and dimensional stabilities. Primary investigations, together with ultra-small angle X-ray scattering, explored the structural integrity of dispersed CNS. The hierarchically dispersed nanofillers provided efficient conductive pathways, offering a systematically varying electrical conductivity with filler concentration. They exhibited excellent dimensional stability even after multiple healing cycles, along with an exceptional stretchability up to 276%. Compared with the pristine matrix, a threefold increase in storage modulus has been observed at the maximum filler loading (15 wt%). They exhibited a commendable balance between the rigidity offered by CNS and excellent matrix flexibility, showing their versatility. As a result of accelerated thermoresponsive bond-exchange reactions, a complete shape recovery with an impressive healing efficiency of 99.6% is observed. This study not only provides a detailed elucidation of a multifunctional system but also offers practical insights for developing highly efficient epoxy-based vitrimers suitable for a wide range of applications.