Chiral phases of lyotropic liquid crystalline cellulose derivatives

An overview is presented of the structure of the chiral nematic lyotropic phase of cellulosetricarbanilate (CTC) and derivatives thereof. The investigated systems show right-and left-handed super-molecular helicoidal structures. The pitch and handedness of these structures was found to be very sensitive to internal and external parameters as temperature, concentration, solvent, kind and position of substituent. By a variation of solvents or substituents a compensated or nematic-like structure may be obtained. The experimental findings for the chiral structure can not be described by current theories.