Record-High Latent Heat, Ultra-Fast Relaxation and Closed-Loop Recycling Double-Brush Polymer Networks for...

Area of Science:

• Materials Science
• Polymer Chemistry
• Thermal Engineering

Background:

• High-performance computing driven by artificial intelligence (AI) requires advanced thermal management solutions.
• Phase change materials (PCMs) are crucial for high-flux thermal management, with ongoing development focused on increasing enthalpy, reducing interfacial thermal resistance (ITR), and improving reliability.

Purpose of the Study:

• To design and synthesize novel double-brush phase-change polymers (PVBS-TMCn) with dynamic crosslinking for enhanced thermal management.
• To fabricate and evaluate a composite material (PVBS-TMC/GF) using these polymers and graphene foam films as thermal interface materials (TIMs).

Main Methods:

• Synthesis of double-brush phase-change polymers (PVBS-TMCn) crosslinked by dynamic B─O─B and Si─O─B bonds.
• Fabrication of a composite thermal interface material (PVBS-TMC/GF) using a stacking-cutting strategy.
• Characterization of material properties including relaxation time, enthalpy, and interfacial thermal resistance (ITR).

Main Results:

• The synthesized PVBS-TMCn exhibited an ultra-fast relaxation time of 0.8 s at 80°C and achieved a record enthalpy of 240.7 J·g⁻¹.
• The PVBS-TMC/GF composite demonstrated self-adaptive modulation of low-ITR in response to temperature changes.
• The composite material showed significantly improved thermal management efficiency compared to commercial products.

Conclusions:

• The novel double-brush polymer topology and dynamic crosslinking effectively enhance enthalpy and minimize loss.
• The PVBS-TMC/GF composite shows promise as an adaptive thermal interface material with superior performance.
• The findings provide fundamental insights for developing advanced phase-change adaptive materials for thermal management applications.