Highly Thermally Conductiveand Flame-Retardant Waterborne Polyurethane Composites with 3D BNNS Bridging Structures via MagneticField Assistance  

作　　者：Hao Jiang Yuhui Xie Mukun He Jindao Li Feng Wu Hua Guo Yongqiang Guo Delong Xie Yi Mei Junwei Gu 

机构地区：[1]Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical Engineering and New Phosphorus Materials,The International Joint Laboratory for Sustainable Polymers of Yunnan Province,The Higher Educational Key Laboratory for Phosphorus Chemical Engineering of Yunnan Province,Faculty of Chemical Engineering,Kunming University of Science and Technology,Kunming 650500,People’s Republic of China [2]Shaanxi Key Laboratory of Macromolecular Science and Technology,School of Chemistry and Chemical Engineering,Northwestern Polytechnical University,Xi’an 710072,People’s Republic of China

出　　处：《Nano-Micro Letters》2025年第6期279-296,共18页纳微快报(英文版)

基　　金：support from the National Natural Science Foundation of China(22268025,52473083,and 22475176);Key Research and Development Program of Yunnan Province(202403AP140036);Natural Science Basic Research Program of Shaanxi(2024JC-TBZC-04);Applied Basic Research Program of Yunnan Province(202201AT070115 and 202201BE070001-031);supported by the Innovation Capability Support Program of Shaanxi(2024RS-CXTD-57).

摘　　要：The microstructure design for thermal conduction pathways in polymeric electrical encapsulation materials is essential to meet the stringent requirements for efficient thermal management and thermal runaway safety in modern electronic devices.Hence,a composite with three-dimensional network(Ho/U-BNNS/WPU)is developed by simultaneously incorporating magnetically modified boron nitride nanosheets(M@BNNS)and non-magnetic organo-grafted BNNS(U-BNNS)into waterborne polyurethane(WPU)to synchronous molding under a horizontal magnetic field.The results indicate that the continuous in-plane pathways formed by M@BNNS aligned along the magnetic field direction,combined with the bridging structure established by U-BNNS,enable Ho/U-BNNS/WPU to exhibit exceptional in-plane(λ//)and through-plane thermal conductivities(λ_(⊥)).In particular,with the addition of 30 wt%M@BNNS and 5 wt%U-BNNS,theλ//andλ_(⊥)of composites reach 11.47 and 2.88 W m^(-1) K^(-1),respectively,which representing a 194.2%improvement inλ_(⊥)compared to the composites with a single orientation of [e-mail],Ho/U-BNNS/WPU exhibits distinguished thermal management capabilities as thermal interface materials for LED and chips.The composites also demonstrate excellent flame retardancy,with a peak heat release and total heat release reduced by 58.9%and 36.9%,respectively,compared to WPU.Thus,this work offers new insights into the thermally conductive structural design and efficient flame-retardant systems of polymer composites,presenting broad application potential in electronic packaging fields.

关 键 词：Boron nitride nanosheets Magnetic response Structural design Thermal conductivity Flame retardancy 

分 类 号：TB3[一般工业技术—材料科学与工程]