Thermal Conducting Channel Based on the Concept of Biological Buffer Compensation System: High Speed and Stable Phonon Transport

ABSTRACT This paper explores the use of modified boron nitride (BN) and carbon nanotubes (CNTs) as fillers for castor oil‐based polyurethane resin. Utilizing vacuum filtration and hot‐pressing techniques, the thermally conductive polysiloxane amino ester was optimized to form high‐speed stable phonon conduction pathways through dynamic covalent bonding and microphase separation, thereby enhancing the heat transfer performance of polymer thermal interface materials (TIMs). The composite material, when filled with 30 wt% of these fillers, exhibits a thermal conductivity ( λ ) of 3.86 W/(m K), representing a 14.86‐fold increase compared to silane‐modified polyurethane ( λ = 0.26 W/(m K)). This thermally conductive polymer demonstrates a tensile stress of 24.2 MPa and an elongation at break of 26.89%, with a volume resistivity reaching 10 ¹² Ω cm. Notably, the thermal conductivity of this composite material also displays exceptional stability, remaining nearly unchanged (< 2.5%) across a wide high and low temperature range, meeting the demands of modern extreme temperature working conditions. This combination of stable high thermal conductivity and insulation properties presents significant potential for applications in thermal management.