| 摘要 |
PROBLEM TO BE SOLVED: To obtain a vibration-damping material exhibiting excellent lightweightness and vibration-damping performance, and useful in e.g. the automotive field by expanding a specific expandable rubber composition under heating so as to express tanδat a specific level or higher. SOLUTION: This vibration-damping material, which is a foam with a tanδof >0.25, is obtained by expanding under heating an expandable rubber composition prepared by compounding (A) 100 pts.wt. of an acrylonitrile-butadiene rubber >=31 wt.% in bound acrylonitrile content with (B) 5-25 pts.wt. of sulfur, (C) 5-200 pts.wt. of a phenolic resin and (D) 5-40 pts.wt. of a foaming agent. This vibration-damping material is capable of exhibiting excellent vibration- damping effect against the flexural or torsional resonance of a structure such as automotive subframe by packing it inside the hollow member of a closed sectional structure affording the above-mentioned structure, also being capable of excluding the propagation of sound running inside the hollow member. |
