GO-enhanced polyurethane phase change materials with triple dynamic bonds: Oxime-urethane, coordination and hydrogen bonds

Traditional crosslinked polyurethane phase change materials face multiple challenges, including poor self-healing ability, low thermal conductivity and insufficient photothermal response. However, existing research has mostly focused on improving single properties, often failing to take into account the comprehensive properties of the material. This study proposes a polyurethane phase change material (GO-Cu 2+ -OUPCMs) based on a “triple dynamic bonds and graphene oxide synergistic strategy.” This material forms a dynamic cross-linked network through hydrogen bonds, oxime-urethane bonds and the coordination bonds formed between Cu 2+ and the oxime-urethane groups, achieving a high self-healing efficiency of 92.10 % while retaining excellent mechanical properties and thermal stability. Graphene oxide (GO) is covalently grafted to the polyurethane network via -NCO groups, enhancing interfacial bonding and significantly improving the material's mechanical strength, thermal conductivity, and phase change enthalpy. In addition, the material exhibits outstanding photothermal conversion capability, enabling rapid thermal response and accelerating the self-healing process. Notably, GO-Cu 2+ -OUPCMs demonstrate remarkable temperature regulation capabilities in lithium battery thermal management, effectively reducing surface temperatures during 3/4C-rate charge/discharge and suppressing thermal runaway. This study systematically elucidates the mechanism of synergistic design between multiple dynamic bonds and functionalized nanofillers, achieving simultaneous enhancement of multiple properties, and providing new insights for the efficient integration and application of polyurethane phase change materials in smart energy storage and thermal management fields.