Lyotropic Liquid Crystalline Structures of Synthetic Polypeptide 2. Measurements of Elastic Constants and Coupling Constants of Poly(γ-Benzyl L-Glutamate) Solutions by the Freedericksz Transition

The object of this report is the determination of material parameters of the lyotropic polymer liquid crystal, poly(γ-benzyl L-glutamate)-1,1,2-trichloroethane solutions, by means of the Freedericksz transition with the magnetic field. The critical field strength H c of the homeotropic polymer liquid crystal was determined in the condition without hysteresis. The bend elastic constant K 33=1.3-1.0×10-11 N and the coupling constant B=4.4×10-6 J m-2 (weight fraction of polymer, w 2=0.173 and 0.138) were obtained from the relations between H c and the cell thickness. The splay elastic constant K 11=1.6×10-11 N (w 2=0.173 and 0.138) was obtained by the simulations of the transition curves. The ratio K 11/K 33 exceeds one and is larger than those of the small molecular liquid crystal.