Pore size and viscoelasticity of acoustic foams
نویسندگان
چکیده
We present linear viscoelastic measurement on a large frequency range (10 to 10 Hz) for cross-linked polymer open cell foams of same density and different pore size. This extend of frequency range is obtained by the validation of Time-Temperature Superposition (TTS) principle, commonly used with polymers. At higher frequencies, the shear moduli are independent on the pore size. In acoustical insulation range (1Hz-16kHz), the shear moduli decrease with the foams pore size. PACS numbers: 43.35. Mr, 43.50. Gf, 43.20. Ye
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تاریخ انتشار 2009