Electrooptical properties of a nematic liquid crystal adsorbed in cellulose membrane

Electrooptical properties of liquid crystal–cellulose membrane composite system have been studied for different pore sizes of the matrix. The optical transmittance of the composite films was observed. The turbidity of the sample can be controlled by application of electric fields exceeding some threshold value. The threshold increases with decreasing pore diameters of the membrane. An observed hysteresis effect is due to the different relaxations of nematic molecules anchored to the surface and in the volume of the pores. An anchoring energy for nematic liquid crystal 4-n-pentyl-4′-cyanobiphenyl (5CB) confined in Synpor membranes of about 7·10−5 J/m2 is estimated from the electric coherence length.