In this work, the viscoelastic behavior of open cell polyurethane foams used in noise control applications is investigated through dynamical mechanical analysis in compression. Several levels of static strains superimposed on a small dynamic one were considered in order to assess the effect material non-linearity on the response. Further, a wide range of frequency and temperatures were explored. At all static strains a master curve could be determined finding a conservative modulus, E’, dependent on the static strain level. Interestingly, the loss factor was the same at all static strains, indicating that the relative contribution of energy dissipation and conservation is unchanged. Moreover, shift factors (and thus the bulk material relaxation times) turned out to be independent on static strain level. These results suggest that the non- linearity of the foam is linked to the change in foam structure with strain rather than to a non-linear behavior of the bulk material. The acoustic performance of the considered materials was modelled for a case study with both standard simulations, performed taking a single value complex modulus, measured at 50Hz and room temperature, as representative of the foam behavior, and with the complex modulus data obtained from the master curves and then compared with experimental results. The transmission loss prediction obtained taking into account the frequency dependence of foams mechanical response is in better agreement with experiments, especially at high frequencies.