Facile orientation of unmodified BN nanosheets in polysiloxane/BN composite films using a high magnetic field
Facile orientation of unmodified BN nanosheets in polysiloxane/BN composite films using a high magnetic field
复制标题
DOI：
10.1007/s10853-010-5075-2
复制
发表时间：
2011-04
影响因子：
4.5
通讯作者：
Hong-Baek Cho;Y. Tokoi;S. Tanaka;Tsuneo Suzuki;Weihua Jiang;H. Suematsu;K. Niihara;T. Nakayama
中科院分区：
文献类型：
--
作者：
Hong-Baek Cho;Y. Tokoi;S. Tanaka;Tsuneo Suzuki;Weihua Jiang;H. Suematsu;K. Niihara;T. Nakayama
通过施加超导磁体产生的强磁场，制备了由高度取向的氮化硼（BN）纳米片在聚硅氧烷中组成的复合膜，而不对BN表面进行改性。通过超声处理将六方BN纳米片分散在聚硅氧烷的预聚物混合物中。然后将均匀的悬浮液浇铸在微米级厚度的聚酰胺间隔物上，并在混合物交联之前施加磁场。聚硅氧烷中的BN纳米片以高各向异性平行或垂直于复合膜平面排列，这取决于磁通量方向。通过控制薄膜中BN纳米片的各向异性，制备的复合薄膜具有增强的热导率。讨论了BN纳米片的旋转机制和复合膜的热扩散机制。
Composite films consisting of highly oriented boron nitride (BN) nanosheets in polysiloxane were fabricated without modifying the BN surface by applying a high magnetic field generated by a superconducting magnet. The hexagonal BN nanosheets were dispersed by sonication in a prepolymer mixture of polysiloxane. The homogeneous suspension was then cast on a polyamide spacer of microscale thickness and a magnetic field was applied before the mixture became crosslinked. The BN nanosheets in the polysiloxane were aligned with high anisotropy either parallel or perpendicular to the composite film plane depending on the magnetic flux direction. The fabricated composite films exhibited enhanced thermal conductivity by controlling the anisotropy of the BN nanosheets in the film. The mechanisms for rotation of BN nanosheets and heat diffusion across the composite film are discussed.