Liquid Crystalline Properties of Cellulose Dervatives(I) -Liquid Crystalline Order of Hydroxypropylcellulose and Acetoxypropylcellulose-

셀룰로오스 유도체의 액정특성(I) -Hydroxypropylcellulose 및 Acetoxypropylcellulose의 액정특성-

The lyotropic liquid crystalline order of cellulose derivatives was studied with the series of cellulose derivatives. The rheological properties of liquid crystalline hydroxypropylcellulose (HPC) and acetoxypropylcellulose (APC) are reported here as a part of these series of studies. The variation of physicochemical state of liquid crystals under dynamic shear conditions were measured with Rheometrics Dynamic Spectrometer (RDS) employing parallel plate geometry. Both HPC and APC showed abrupt changes of the measured values such as tanδ, G'/2G", and n' in the vicinity of critical (C*) and saturated (Cs) concentrations. At low frequencies, both two lyotropic systems exhibited a decrease of loss factor with concentration. At high frequencies, however, loss factor was increased at higher concentrations, which may be attributed to a significant deformation of orientational order of liquid crystalline domain.