Polymer, Vol.37, No.6, 893-901, 1996
Time-Resolved in-Situ X-Ray-Scattering Studies of Aqueous Hydroxypropylcellulose Solutions
The evolution of the global orientation parameter for a series of aqueous hydroxypropylcellulose solutions both during and following the cessation of a steady-state shear Bow is reported. Time-resolved orientation measurements were made in situ through a novel X-ray rheometer coupled with a two-dimensional electronic X-ray camera, and using an intense X-ray source at the LURE synchrotron. After the cessation of flow, the global orientation decreases from the steady state orientation level to zero following shear flow at a low shear rate or to a small but finite value after flow at a high shear rate. The decrease of orientation with time shows different behaviour, dependent upon the previously applied shear rate.
Keywords:POLYMER LIQUID-CRYSTALS;ANGLE LIGHT-SCATTERING;RODLIKE POLYMERS;SHEAR-FLOW;NEMATIC SOLUTIONS;ARAMID SOLUTIONS;BAND TEXTURES;RHEOLOGY;TRANSIENT;PHASE