  An equivalence between an integro-differential operator M and an evolution
operator Ln is determined. From this equivalence the fundamental solution of Ln
is estimated in terms of the fundamental solution related to the third-order
operator L1 whose behavior is now available. Moreover, properties typical of
wave hierarchies can be applied to polymeric materials. As an example the case
n= 2 is considered and results are applied to the Rouse model and the reptation
model which describe different aspects of polymer chains.
