Observation of a soft mode of elastic instability in liquid crystal elastomers.
In monodomain liquid crystal elastomers a symmetry-breaking locked-in anisotropy causes a semisoft elastic response characterized by a plateau in the stress-strain curve. We show by dynamic light scattering performed as a function of deformation that the relaxation rate of the nematic director fluctuations decreases with strain to a very small value at the onset of the soft elastic response, revealing the existence of a dynamic soft mode. The results are in complete agreement with the theory of semisoft elasticity and allow us to determine all the constants of the model.
Jozef Stefan Institute, Jamova 39, Ljubljana SI-1000, Slovenia.
Andrej
A
Petelin
Martin
M
Copic