抄録
We study the relation between the shape anisotropy changes, Δα, and the optical birefringence, Δn, of dry and swollen rigid bi-functionally (8.0 mol %, 8A2) and flexible tri-functionally [5 mol % (5V3) and 7 mol % (7V3)] cross-linked liquid single crystal elastomers (LSCEs) as a function of temperature. 4-n-pentyl-4-cyanobiphenyl (5CB) is used as the solvent. Plotting Δα as a function of Δn, a linear dependence is observed for all LSCE samples. This indicates that Δα results from the liquid crystal ordering. The largest Δα (∼0.2 at T=30 °C) is observed in dry 8A2, which has a large frozen-in orientational order (FOO). The swollen samples show much smaller Δα, ∼0.03–0.05, because of a smaller modulus elasticity after the swelling process.
