Abstract
The phase diagrams of Brij 97/(PEO)m(PPO)n(PEO)m/water/IPM quaternary systems (A L‐64: m=13, n=30; A L‐62: m=7, n=32; A L‐61: m=3.5, n=31) were determined at 25°C. The liquid crystalline phases (lamellar Lαand hexagonal H1) were investigated by means of small angle x‐ray scattering (SAXS) and rheological techniques, with comparison of composition and component effects. The lamellar phases formed in Brij 97/A L‐64 and Brij 97/A L‐62 systems array more orderly than that of Brij 97/A L‐61 system, indicated by the stronger intensity of the second reflection peak in the SAXS patterns and the higher moduli (G′ and G″) in the dynamic rheograms. In Brij 97/A L‐64/water/IPM system, all Lα phases exhibit elastic rheograms, moreover the viscous property get increased with increase in water content. On the other hand, with this change, the H1 phases show Maxwell and gel‐like rheograms in order, in which the latter shows mechanical and relaxation spectra typical of highly structured materials.
Support of this work by the Natural Science Fund of Shandong Province (Y2006B29) and the Natural Science Fund Foundation of China (Grant 60671010, 20676051) is gratefully acknowledged. The authors also would like to thank Dr. Yongfu Wu, PEER Center, California Institute of Technology, for valuable discussions.