Fabrication of boron nitride reinforced carboxymethyl modified lignin-based re-crosslinkable hydrogel with excellent heat dissipation ability.

[Display omitted] • Carboxymethylation of lignin created more reactive sites to form hydrogel. • Incorporation of PDA@BN in the hydrogel improves the heat dissipation capability. • Employment of 3-ABA imparts the hydrogel with re-crosslinkable ability. • The recrosslinked hydrogel maintains excellent temperature resistance. In this work, a series of re-crosslinkable hydrogels comprising carboxymethylated lignin, PVA and 3-aminophenylboronic acid (3-ABA) was successfully synthesized. Incorporation of polydopamine (PDA) coated boron nitride (PDA@BN) endowed the hydrogel with significantly improved heat dissipation ability, mechanical strength and swelling resistance. The hydrogel containing 20 % of PDA@BN, namely Gel-20 %BN displayed an initial degradation temperature of 131 ℃ and a high thermal conductivity of 3.74 W/m·K, surpassing a plethora of different biobased hydrogels. Gel-20 %BN maintained stable morphology even under continuous heating at 200 ℃ for 15 min and exhibited low surface temperatures without undergoing melting or decomposition, thus demonstrating remarkable heat dissipation capability. The re-crosslinked hydrogel, referred to as Re.Gel-20 %BN, retained similar performance to Gel-20 %BN, maintaining excellent heat dissipation characteristics and stability at 130 ℃ over an extended period. Further investigation is warranted to explore degradation or recovery methods of this hydrogel in reservoir conditions, aiming to minimize the environmental impact of petroleum extraction and contribute to a greener and more sustainable oil production process. [ABSTRACT FROM AUTHOR]