Fabrication of controlled linear assemblies of graphite nanosheets in polysiloxane-based nanocomposite films and enhancement of thermal property

H.-B. Cho, S. Yanahara, T. Nakayama, H. Suematsu, T. Suzuki, W. Jiang, S. Tanaka, K. Niihara
Nagaoka University of Technology, JP

Keywords: thermal property, graphite nanosheet, nanocomposite, self-assembly, orientation


In the present research, we report successful control of orientation and relocation of GNs in polymer matrix using electric and magnetic fields inducing external torques. According to modulation of the external torque, GNs can establish end-to-end attachment anchoring film surfaces by self-assembly, and the intensity of the linear assembles of GNs (LAGNs) are modulated. And the relationship between the LAGNs structure and enhancement of thermal property of the composites are investigated. AC, DC, switching DC electric fields, and magnetic fields are applied for the controlled orientation of GNs in polymer matrix. We confirmed that the orientation of GNs, which is perpendicular to the composite surfaces are well controlled by both electric and magnetic fields, and the orientation itself could more enhanced by applying magnetic field rather than electric field. However, it was confirmed that the GNs could establish self-assembled LAGNs (by cross-sectional digital micrographs, not posted here), which enhanced the thermal diffusivity of the fabricated composite rather than composite with orientation but not with self-assembly. The mechanisms for fabrication of LAGNs and enhancement of thermal diffusivity will be elucidated.