Abstract:Holographic polymer dispersed ionic liquid (HPDIL) with transmission grating structures was fabricated through holography, utilizing the homogeneous mixture composed of a photoinitibitor, monomers and the ionic liquid (IL) named 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide. The effect of IL content on the system viscosity, photopolymerization kinetics, degree of phase separation, optical properties and ionic conductivity of HPDIL was investigated systematically. With an increase of the IL content from 20 to 60 wt%, the mixture viscosity increased from 6.9 to 25.3 mPa·s. Upon exposure to 442 nm monochromic light with an intensity of 20 mW/cm2 for 1200 s, the overall double-bond conversion of monomers decreased from 39% to 18% when increasing the IL content from 20 to 60 wt%, primarily because of the increased viscosity. The diffraction efficiency of HPDIL increased from 0 to 70.5% with increasing the IL loading from 20 to 60 wt% and then decreased to 55.0% when further increasing the IL content to 70 wt%. The maximum refractive index modulation was 12.3 × 10-3 with 60 wt% of IL. The maximum degree of phase separation reached 38.2% when adding 50 wt% of IL. The HPDIL was able to be applied as solid electrolyte with anisotropic ionic conductivity. The ionic conductivity along the direction parallel to the gratings of HPDIL could be 2.7 times higher than that of the perpendicular direction. This study pays a way to construct anisotropic polymer electrolyte.