Nonlinear Viscoelasticity in Long-Time Relaxation Process of Disperse Systems of Solid Particles

Abstract

Linear and nonlinear viscoelastic properties of disperse systems of photosensitive particles were studied in relation to the degree of aggregation of dispersing particles. The disperse system has the characteristic long-time relaxation process attributed to the aggregate structure of dispersing particles. In that relaxation process, the system in which the dispersing particles aggregate in some degree shows markedly nonlinear viscoelasticity. The characteristic relaxation time in the long-time relaxation process can be closely related with the rotational diffusion of the aggregate. It is also shown that the characteristic relaxation time is independent of the dynamic strain amplitude.