The number of polyurethane based laminate layers and assembly effect on its sound absorption

Noise pollution is one of the disadvantages of industrial development and urbanization, which has attracted the attention of academic and industrial researchers since ۱۹۷۰s, pursuing them for solving the problem in one way or another. In this research, flexible Polyurethane based foam, ۳۵ wt. % of MDI and appropriate polyol composition, with porous and tortuous structure carrying open cells with viscoelastic shells were synthesized for insulation and sound absorption. Later, the synthesized single layer PU based foam, ۱۰ mm in thickness, were sandwiched between two layers of commercial PU layers with backup adhesive, ۵ mm in thickness. The acoustic properties of single and three layers hybrid insulators were evaluated with impedance tube simulator based on the transmitted sound loss in terms of frequency

کلیدواژه ها:

Polyurethane foam ، tortuous path ، Integrated three layers hybrid ، sound absorption