  In this paper we discuss a family of viscous Cahn-Hilliard equations with a
non-smooth viscosity term. This system may be viewed as an approximation of a
"forward-backward" parabolic equation. The resulting problem is highly
nonlinear, coupling in the same equation two nonlinearities with the diffusion
term. In particular, we prove existence of solutions for the related initial
and boundary value problem. Under suitable assumptions, we also state
uniqueness and continuous dependence on data.
