Enhanced tough recyclable hemiaminal dynamic covalent network with boron nitride composites material with high thermal conductivity at low filler content

Abstract

The demand for thermal interface materials (TIMs) with outstanding heat dissipation capability is increasing due to the advancements of multifunctional, miniaturized and well-integrated electronic devices. Simultaneously, as the accumulation of e-waste continues to grow, the recyclability of TIMs has emerged as a pressing concern. Herein, we introduce a novel approach that combines flow casting and hot pressing to create a tough recyclable hemiaminal dynamic covalent network with boron nitride composites film, which shows exceptional recyclability and high thermal conductivity. This approach was accomplished by combining hemiaminal dynamic covalent networks (HDCNs) with ionic liquid crystal exfoliated boron nitride nanosheets (ILC(Cl)-BNNS) via in situ polymerization. The obtained HDCN/BNNS composites film can enjoy a remarkable in-plane thermal conductivity of 2.72 Wm−1K−1 under a BNNS loading of 9.00 wt%, thus achieving an impressive ≈1195% in thermal conductivity enhancement. Furthermore, the HDCN/BNNS composite film enables the recycling of the composites under mild conditions, resulting in the facile recovery of BNNS with nearly pristine morphology and an impressive yield of 72.50%. This work presents a novel approach for the design of recyclable and high-performance TIMs, offering promising prospects for future applications.