An original investigation is presented on the sound absorption and acoustic impedance, in some polymer materials. By using the steady waves method we have computed and measured experimentally the sound energy absorption coefficient as a function of frequency, at constant temperature. The numerical results are comparatively analyzed in order to establish their practical relevance and usefulnes. The values for acoustic impedance components indicate the nature of the dissipative phenomena that accompany sound propagation. For the case of rubber, one can notice an absorption increase as an effect of vulcanization through which the structure of the polymer is modified. The impurities that are part of the internal composition of the substances under study have an important influence on the physical quantities that we are analyzing. By making measurements at different temperatures one can get additional informations about sound absorption mechanisms.
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