Interfacial engineering of MOF functionalized BN networks for preparation of polyurethane-based phase change composites with excellent thermal conductivity and thermal management properties

Dual heat-conduction pathways significantly enhance thermal transport. • In situ MOF growth is achieved on surface-modified BN fillers. • Interfacial functionalization improves filler-matrix compatibility. The heat transfer of electronic devices requires the use of thermal interface materials (TIM) with high heat dissipation capabilities and excellent thermal management performance to prevent overheating. However, in polymer-based thermal conductive phase-change composite systems, simple blending of functional nanofillers will lead to interface incompatibility, which cannot fully utilize the unique advantages of the fillers. Herein, a flexible polyurethane (PU)-based boron nitride/metal-organic framework/polyethylene glycol (BN/MOF/PEG) composite film (named BMP) is fabricated which integrates high latent heat and excellent thermal management capabilities via functional modification and the construction of dual heat conduction pathways. After sucrose treatment of BN, hydroxyl-functionalized BN (BN-OH) was obtained. Subsequently, MOF was in situ grown on the BN-OH surface to form BM, which was further deposited onto BN-OH/PU (TB) fibers for PEG adsorption, thereby yielding the BMP composite film. Among them, the thermal conductivity of the BMP-3 film reach 2.2 W·m −1 ·K −1 , and the latent heat retention rate reach 70%. Compared with commercial silicone grease, the developed BMP film can significantly reduce the full-load CPU temperature by 19 °C when with a heat sink, demonstrating excellent thermal management capabilities. Additionally, combining molecular dynamic and quantum chemistry simulations, the influence of functionalized modified nanofillers on the interface regulation was characterized from a microscopic perspective. This work provides a theoretical basis for designing advanced TIM materials with high latent heat and excellent thermal management capabilities, and is expected to promote the iterative update of the thermal management part of electronic devices. Download: Download high-res image (271KB) Download: Download full-size image