The potential of boron nitride nanosheets(BNNS)in thermal management materials is significantly hindered by the inherent surface chemical inertness that leads to a substantial interfacial thermal resistance.To overcome this limitation,hydroxyl-functionalized boron nitride nanosheets(BNNS-OH)were successfully synthesized through a high-temperature alkali treatment coupled with liquid-phase assisted ultrasonication.Subsequently,a vacuum filtration combined with compression drying technique was employed to fabricate BNNS-OH/CNF composites.The hydroxyl groups on the surface of BNNS enhance compatibility with CNF and improve the dispersion of BNNS,thereby reducing the interfacial thermal resistance.Furthermore,the one-dimensional structure of CNF does not fully cover the thermal fillers,and the compression drying method effectively minimizes the voids between the fillers and polymer,resulting in a dense layered structure.This facilitates better contact between fillers,forming continuous thermal conduction pathways and enhancing the thermal conductivity of the composite material.When loaded with 30wt％BNNS-OH,the thermal conductivity of the BNNS-OH/CNF composite reaches as high as 14.571 W·m-1·K-1,approximately 819％higher than that of pure CNF films.In practical heat dissipation applications,compared to CNF films,LED chips encapsulated with BNNS-OH/CNF com-posite films exhibited a temperature reduction of 29.5℃ within 150 s.
NETL
NSTL
万方数据
