Epoxy-Based Vitrimer/GNP Nanocomposites: Unleashing Superior Shape Recovery and Multifunctional Properties

Abstract

Vitrimers are revolutionizing the polymer industry with their extraordinary ability to be recycled, repaired, and reshaped, making them a promising alternative in several applications, including the aerospace and electronic industries. Recently, interconnected structures of 2D materials have been explored to overcome agglomeration and boost the thermal and electrical conductivity of polymer nanocomposites. In this study, we engineered a low-viscosity polymer grade to promote the high-quality infiltration of graphene foams produced via freeze-drying. The neat vitrimer and the vitrimer/GNP foam nanocomposite were characterized with respect to mechanical, thermal, and electrical properties, particularly, shape recovery under different stimuli methods: hot water, hot plate, and electrical current. The nanocomposite resulted in a rapid shape recovery, surpassing the neat vitrimer across all conditions, particularly where conduction dominated heat transfer. When compared with the neat vitrimer, adding graphene resulted in ∼6% and 36.3% increases in elastic modulus and tan δ, respectively, while thermal and electrical conductivity improved by 6-fold (1.09 W m^–1 K^–1) and 10 orders of magnitude (0.043 S cm^–1), respectively. These findings underscore the exceptional capabilities of an interconnected reinforced phase within a polymer matrix. Furthermore, for the case of shape-memory polymers/vitrimers, the addition of graphene diversifies the stimuli options for shape recovery in electrically insulating matrices.