Highly efficient holographic PDLC based on acrylate monomers with low functionality

The transmission holographic gratings were recorded by two coherent beams of Ar-laser (lambda_514 nm) in the liquid crystal (LC) - prepolymer composition with prepolymeric component based on acrylic monomers of low functionality (f <= 3). The diffraction efficiency of these gratings was studied as a function of recording conditions (exposure intensity and time) and applied voltage. In parallel, morphology of the obtained samples was investigated. It is shown that compositions based on acrylic monomers with f <= 3 may yield holographic gratings with good characteristics (high diffraction efficiency, low scattering loss, good electrooptic performance), approaching those described for monomers with higher functionality. Besides, we observed difference in morphology of samples based on monomers with functionality 2 and 3; they show conventional and inverse morphology, respectively.