Development of Flexible Sound-Proof Materials

Abstract

In recent years, the noise, one of environment problems, has been paid more attention. And the utilization of the high performance sound-proof materials is an effective method to solve the problem. However, traditional sound insulation materials, mostly made from concrete and plumbum, are of high hardness, heavy and difficult for design. In this paper, flexible sound-proof materials made from glass fabric reinforced polyurethane (PU) resin were developed. To maintain the soft features and effectiveness of particulate fillers, we used the PU resin filled with silica particles only in its hard segments. Both the sound-proof performance and flexural ability for the developed materials were evaluated. As a result, the influence of the silica content on material properties and the transmission loss were clarified. Although the increment of silica content may decrease the flexural ability and increase the loop hardness even up to 50%, the loop hardness was about 1N, which still indicated the excellent flexibility. The effectiveness of the PU hybrid with hard segments of silica particles on the sound-proof behavior was confirmed and this resulted in the developed materials with high performance of sound-proof even for very thin and low area density one. The influence of the silica content and area density on both flexible ability and sound performance are also made clear. Furthermore, the prediction of transmission loss is conducted and a good agreement with the experimental results was obtained.