TEXTURES DURING RECOIL OF ANISOTROPIC HYDROXYPROPYLCELLULOSE SOLUTIONS

The recoil of anisotropic hydroxypropylcellulose solutions was studied by optical microscopy and light scattering. Different stresses were a pplied before stopping the flow and observing the recoil. At low stres s levels, the scaling of the recoverable strain versus scaled relaxati on time applies. A change of texture is noticeable only after most of the strain has been recovered. At a high stress level, a band texture appears during recoil. The appearance of this band texture stops the r ecovery process until the band texture disappears, and the recovery pr ocess then continues. The presence of a band texture during recoil is shown to promote a larger recoil. (C) 1998 The Society of Rheology.[S0 148-6055(98)00202-8].