Relation between thermal conductivity and molecular alignment direction of free-standing film aligned with rubbing method



The liquid crystal acryl compounds, in which the molecular directions were aligned by the rubbing method, were polymerized by UV irradiation, to provide the free-standing aligned films of 200-μm thickness. The relation between the thermal conductivity and the aligned molecular direction of the films was investigated. The homogeneous film showed the largest magnitude of the thermal conductivity at the direction along the molecular long axis (0.69 W/m K). This was 3.6 times greater than that of poly(methyl methacrylate). The thermal conductivity was dependent on the rotation angle and the concentration of the homogeneous molecular long axis fractions in the networks. These relations were investigated with the twisted film. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3591–3599, 2005