Thermally Functional Liquid Crystal Networks by Magnetic Field Driven Molecular Orientation

详细信息    查看全文

• 作者：Jungwoo Shin ; Minjee Kang ; Tsunghan Tsai ; Cecilia Leal ; Paul V. Braun ; David G. Cahill
• 刊名：ACS Macro Letters
• 出版年：2016
• 出版时间：August 16, 2016
• 年：2016
• 卷：5
• 期：8
• 页码：955-960
• 全文大小：384K
• 年卷期：0
• ISSN：2161-1653

文摘

Aligned liquid crystal networks were synthesized by photopolymerization of liquid crystal monomers in the presence of magnetic fields. Grazing incident wide-angle X-ray scattering was used to characterize the degree of molecular alignment of mesogen chains and time-domain thermoreflectance was used to measure thermal conductivity. Liquid crystal networks with mesogenic units aligned perpendicular and parallel to the substrate exhibit thermal conductivity of 0.34 W m^–1 K^–1 and 0.22 W m^–1 K^–1, respectively. The thermal conductivity and orientational order of liquid crystal networks vary as a function of temperature. The thermal conductivity of liquid crystal networks can be manipulated by a magnetic field at above the glass transition temperature (65 °C) where the reduced viscosity enables molecular reorientation on the time scale of 10 min.