DYNAMIC YOUNG MODULUS AND LOSS FACTOR OF PLASTIC FOAMS FOR IMPACT SOUND ISOLATION

The frequency and amplitude dependences of the dynamic Young's modulus and loss factor of polystyrene (PS) and polyethylene (PE) foams usable for impact sound isolation in floating floors, measured at room temperature, in the frequency range of 100-3000 Hz, and in the range of strain amplitude of 10(-5)-10(-1), respectively, are given in the paper. It is shown that the frame loss factor of the PS and PE foams is low (similar to 0.01 and similar to 0.1, respectively), and that of the foam sheets including air is also low (similar to 0.1). The frame dynamic Young's modulus of both foams slightly increases with frequency. The dynamic behaviour of the foams is linear up to the strain amplitude of about 10(-3), above which the dynamic Young's modulus decreases, whereas the loss factor increases with increasing strain.