Stress relaxation under large deformation and transient viscoelastic properties of carbon black-linseed oil suspensions were investigated using a cone and plate type rheometer.The equilibrium moduli in the long time region were observed in stress relaxation curves even under a large shear strain such as 6.0 shear unit, and these values exhibited a remarkable strain dependence. These phenomena may be attributed to the formation of close structural networks of carbon black particles in linseed oil.Shear stress development after sudden initiation of steady shear flow showed a overshoot and approached a steady-state value. This transient phenomenon seems to be caused by the break down of the structure of dispersed particles by shearing stress. Under steady flow conditions, the structural networks were destroyed completely. Therefore, the equilibrium values could not be observed in the stress relaxation curves after cessation of the steady flow.
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