- Volume 52 Issue 4
Two kinds of polyurethane elastomers were prepared and their acoustical properties underwater investigated. Their dynamic mechanical properties were measured using a dynamic mechanical analyzer. The sound speed and echo reduction in the 1-50 kHz frequency range were calculated from the data obtained using the analyzer. The sound speed, transmission and attenuation cofficient in 300-800 kHz were measured in a water-filled tank. Impedance tube experiments were performed to determine the reflective coefficient and echo reduction in the 3-8 kHz range. The polyurethane elastomer containing a hollow glass sphere showed a lower reflective coefficient and a higher echo reduction than the polyurethane elastomer without a filler.
polyurethane elastomer;dynamic mechanical properties;sound speed;echo reduction;attenuation constant
- M. L. Williams, R. F. Landel, and J. D. Ferry, ''Mechanical properties of substances of high molecular weight. 19. The temperature dependence of relaxation mechanisms in amorphous polymers and other glass-forming liquids,'' J. Am. Chem. Soc., 77, 3701 (1955). https://doi.org/10.1021/ja01619a008
- J. Jarzynski, ''Mechanisms of Sound Attenuation in Materials,'' in Sound and Vibration Damping with Polymers, edited by R. D. Corsaro and L. H. Sperling, ACS Symposium Series 424, American Chemical Society, Washington, DC, 1990.
- R. J. Bobber, "Underwater Electroacoustic measurements", pp. 287-313, Peninsula Publishing, Los Altos, CA, 1988.
- M. P. Hageberg and Robert. D. Corsaro, "A Samll Pressurized Vessel for Measuring the Acoustic Properties of Materials", J. Acoust. Soc. Am., 77, 1222 (1985). https://doi.org/10.1121/1.392189
- L. L. Beranek, "Acoustical Measurements", American Institute of Physics, Woodbury, NY, 1988.
- ASTM C384-558, 1972 and E1050-90 "Standard Method of Test for Impedance and Absorption of Acoustic Material by the Tube".
- W. Sun, X. Yan, and X. Zhu, "Dynamic Mechanical and Underwater Acoustic Properties of the Polyurethane/Epoxy Resin Blend Elastomers Filled with Macroporous Poly(vinyl acetate-co-triallyl isocyanurate) Resin Beads", J. Appl. Polym. Sci., 122, 2359 (2011). https://doi.org/10.1002/app.34112
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