Acoustic properties of nitrile butadiene rubber for underwater applications

Abstract

Acoustic properties of nitrile butadiene rubber (NBR) specimens with carbon black as filler were investigated with different sulfur contents in the frequency range of 300-1000 kHz. Their mechanical properties, such as density, hardness, tensile strength, were conventionally measured and correlated with their acoustic properties. Sound speeds in the specimens were increased with an increase in the sulfur content. The variation of sound speed was about 2-5% in the specimens, whereas the variation of density was less than 0.4%. Enhanced acoustic transmission was also observed with increasing sulfur content. It may be due to the hardness change from the increase of crosslinking density in the specimens. These results show that the mechanical properties of NBR can be nondestructively and accurately determined with the acoustic property measurements. By use of the desired mechanical and acoustic properties, the utilization of the NBR for underwater applications becomes less difficult.

Carbon black effect on the acoustic properties of nitrile butadiene rubber

“…Acoustic properties of nitrile butadiene rubber (NBR) with the content variation of vulcanizing agent sulfur were recently reported by Jung et al8 In their study, an increase of the sulfur contents resulted in the increase of the crosslinking density, and the increase of the sound speed and resulted in the increase of acoustic wave transmission.…”

“…Figure 7 shows the squared sound speed as a function of hardness/density, ( s /ρ s ), where s and ρ s are the hardness and the density of specimen, respectively. The open square symbols show the specimens of carbon black content variation (NC series) and the solid circle symbols show the specimens of sulfur content variation (NS series) 8. Both ( s /ρ s ) dependences of the squared sound speeds of NC series and NS series show linearly increased trends, but the variations are clearly different.…”

“…In this study, the mechanical and acoustic properties of the NBR with constant sulfur content were measured with the carbon content variation. They are also compared with those of NBR with the sulfur content variation 8…”

Mechanical and acoustic performance prediction model for elastomers in different environmental conditions

“…22,23 The researchers also investigate the acoustic properties for elastomers for various structures. 24,25,26 Elastomers have the characteristics of both elastic solid and viscous fluid. Therefore, microscopic chains of elastomers always cause acoustic energy loss by internal friction and resonance 27,28 which are affected by temperature and pressure especially for underwater conditions.…”

The Effects of Various Additive Components on the Sound Absorption Performances of Polyurethane Foams

“…The pore size distributions and microscopic structures of the acoustic materials significantly affected the sound absorption performance. Caviglia and Morro [20] and Jung et al [21,22] studied the sound properties of multilayered viscoelastic foams with planar interfaces and Yang et al [23] reported the sound properties of the multilayered viscoelastic composites with different interface shapes. Chen et al [24] investigated the effects of the surface shapes and sizes of the porous materials with perforated plates on the acoustic absorption by using the finite element procedure.…”