The kinetics of holographic recording of diffraction grating into thin films of a light-sensitive monodomain liquid crystal elastomer shows an irregular oscillatory behavior attributed to contraction of the film during the recording process. At temperatures far below the nematic-isotropic phase transition, the spontaneous erasure kinetics exhibits exponential relaxation with relaxation time following the Arrhenius activation law. However, at temperatures close to the nematic-isotropic phase transition, the erasure process shows an interesting nonmonotonic behavior that we attribute to the non-linear relation between the concentration of the photo-transformed chemical groups and the nematic order parameter.
COBISS.SI-ID: 25765927
The orientational order parameters of UB-d(4) [1,4-bis(undec-10-en-1-yloxy)benzene-d(4)] in the ZLI1167 nematic mixture are studied by means of H-2 NMR at variable temperature. UB-d(4) is a typical crosslinker in liquid crystal elastomers (LCEs). We infer that the biaxial order parameter of the crosslinker in the LCE matrix is low enough to be neglected. The crosslinker UB-d(4) is a reliable probe to monitor the nematic order in the LSCE-UB-d(4) sample.
COBISS.SI-ID: 25573927