Abstract
Unstable flows of liquid crystalline polymers in slit flow cells are studied using a 50wt% aqueous solution of hydroxypropylcellulose. The wavy texture pattern is observed in the downstream region far from the entrance of the flow cell regardless of the geometry of cell entrance. The cell thickness significantly affects the structure of the wavy texture, and its wavy length increases with increasing cell thickness. Furthermore, the dichroism measurement is carried out to examine the development of molecular orientation in the flow cell with an abrupt expansion entry. In the region where the wavy texture exists, the molecules align in the direction of the flow on the average over the cell thickness.
