全息聚合物分散离子液体的制备及性能

Formulation and Properties of Holographic Polymer Dispersed Ionic Liquid

以光引发阻聚剂、光聚合单体和离子液体1-丁基-3-甲基咪唑啉双(三氟甲基磺酰基)亚胺组成的混合液为原料,通过激光全息曝光,制备了透射式全息聚合物分散离子液体(HPDIL)。研究了离子液体质量分数对体系黏度、光聚合反应动力学、相分离程度、HPDIL光学性能及导电特性的影响。结果表明:当离子液体质量分数从0.2增加至0.6时,体系黏度从6.9mPa·s升高至25.3mPa·s,光照1 200s后的双键转化率从39%降低至18%。随着离子液体质量分数的增加,HPDIL的衍射效率先升高后降低。当离子液体质量分数为0.6时,HPDIL的衍射效率达到峰值70.5%,折射率调制度达到12.3×10^(-3)。当离子液体质量分数为0.5时,体系的相分离程度达到峰值38.2%。HPDIL具有导电各向异性,当离子液体质量分数为0.6时,HPDIL条纹平行方向的电导率可达垂直方向电导率的2.7倍。

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 effects of IL mass fraction on the system viscosity,photopolymerization kinetics,degree of phase separation,optical properties and ionic conductivity of HPDIL were investigated systematically.With an increase of the IL mass fraction from 0.2 to 0.6,the mixture viscosity increased from 6.9 mPa·s to 25.3 mPa·s.Upon exposure to 442 nm monochromic light with an intensity of 20 mW/cm 2 for 1 200 s,the overall double-bond conversion of monomers decreased from 39%to 18%when increasing the IL mass fraction from 0.2 to 0.6,primarily because of the increased viscosity.The diffraction efficiency of HPDIL increased from 0 to 70.5%when increasing the IL mass fraction from 0.2 to 0.6,and then decreased to 55.0%when further increasing the IL mass fraction to 0.7.The maximum refractive index modulation was 12.3×10-3 with 0.6 of IL mass fraction.The maximum degree of phase separation reached 38.2%when the mass fraction of IL was 0.5.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 as much as that along the perpendicular direction when the mass fraction of IL was 0.6.