On some remarkable properties of an extended thermodynamic model for dense gases and macromolecular fluids

Recently, the 14 moments model of extended thermodynamics for dense gases and macromolecular fluids has been considered and an exact solution, of the restrictions imposed by the entropy principle and that of Galilean relativity, has been obtained without using Taylor's expansions. Here, we prove the uniqueness of the above solution and exploit other pertinent conditions such as the convexity of the function h' related to the entropy density, the problem of subsystems and the fact that the flux in the conservation law of mass must be the moment of order 1 in the conservation law of momentum. The results present interesting aspects which were not suspected when only approximated solutions of this problem were known.