Abstract
In the present study, the conditions related to the irreversible physical gel formation of cm size are quantitatively investigated by applying shear and extensional deformation to the surfactant solution by dosing through meshes, together with image analysis based on observation results. Dynamic viscoelasticity measurements were performed using a rheometer to clarify the rheological properties of the FIS gels, and relaxation times were also calculated using the Maxwell model.
From the observation results, it was confirmed that the solution sank in a lumpy state in four out of twelve conditions. The solution remained lumpy for up to fifteen minutes, indicating that it was an irreversible physical gel. Furthermore, the results of image analysis by luminance values of the observation movies over time provided high luminance values for the condition of the gel formation. The dynamic viscoelasticity measurement showed solid-like properties in a wider frequency band of the condition of the gel formation. Moreover, the relaxation time was 4.5–11.8 s. From the observation, dynamic viscoelasticity measurement, and relaxation time, the dosed fluid with an irreversible gel showed solid-like properties for a long time.