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The equilibrium statistics of temporary polymer networks, developed in part I of this work, is extended to the nonequilibrium situation. The (generalized) diffusion equation within the (generalized) spring-bead model is simplified by the relaxation-time approach. A transcendental formula for the calculation of the relaxation times which govern decay and reformation of junctions is derived in the one-junction approximation. The relaxation times are determined by chain lengths and local elastic energy.The numerical calculation of the relaxation times requires a computer program of moderate extent. Using these relaxation times, the simplified diffusion equation is solved for the second moments by which the stress tensor can be related to the velocity gradient tensor. Results of the calculations will be reported in part III of this work where, in particular, the viscoelastic behaviour of temporary networks will be predicted and the results will be compared with available experiments.The present paper ends with a brief but complete description of the numerical program (appendix II). This program contains all input data and subprograms required to calculate numerically the stresses and material functions of the considered polymer solution.

The spatial orientation of rigid ellipsoidal particles was analyzed as proceeding in a dilute solution flowing in a velocity field with parallel gradient, i.e., in a field characterized by the deformation rate tensor: On the basis of general relations given by Jeffery, the hydrodynamic equations of motion of a single ellipsoid were obtained as Ψ = 0, φ = 0, θ = −¾qR sin 2θ, where q = ∂Vκ/∂κ is the parallel velocity gradient and R = (a2 − b2)/(a2 + b2) is the shape coefficient of ellipsoids. Considering the action of velocity field and that of Brownian motion (rotational diffusion), a distribution density function ρ(t, θ) was derived, which describes the spatial orientation of the axes of symmetry of the ellipsoids: where is the steady‐state distribution. In a similar way, the axial orientation factor f0 = 1 − 3/2 sin2θ was obtained:

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