Study on the Design and Sound Absorption Performance of Low-pollution Automotive Polyurethane Foam

Polyurethane foam is one of the most commonly used sound absorbing materials in automobiles. In the existing research, organic solvents are included in the formula of polyurethane foam, which has certain pollution property. Therefore, this work mainly designs low-pollution polyurethane foam materials and studies its sound absorbing performance. The new formulation of low-pollution polyurethane with no organic solvent was adopted, and the formulation was optimized by four factors and three levels orthogonal experiment. The polyurethane foam was synthesized by one-step method, and then LMS Test.Lab and impedance tube equipment were used to test and analyze the sound absorption properties of the materials. The low-pollution polyurethane foam can not only reduce the content of volatile organic compounds in automobile interior, but also show good sound absorption performance. Its average sound absorption coefficient is 0.581, and the peak absorption coefficient is 0.962. The influe-nce of structural parameters of low-pollution polyurethane foam on the sound absorption performance was studied by using the circular pipe theoretical model. When the porosity is 0.7 and the material thickness is less than 65mm, the sound absorption property of the polyurethane foam increases with the increase of the porosity and the thickness of the material; however, the change of flow resistance has little effect on the sound absorption of the material. © 2022, Materials Review Magazine. All right reserved.