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通过驻波管法测试不同隔音垫聚氨酯软质高回弹泡沫的吸声系数,结合显微镜对泡沫的力学特性和形态进行观察和分析。研究结果表明,泡沫在低频区的吸声系数随厚度的增加而提高,而在高频区则有所减弱;泡沫的吸声系数随密度增加而提高;泡孔形态对泡沫的吸声性能有显著影响,细密而均一的泡孔有利于声能的吸收;不同异氰酸酯由于反应性和结构上的差异,泡沫也表现出不同的吸声特性;高压发泡生产的泡沫峰值吸声频率稍向高频区移动,复合乙烯–醋酸乙烯共聚弹性体(EVA)后泡沫的峰值吸声频率稍向低频区移动。
Through the standing wave method, the sound absorption coefficient of polyurethane flexible high resilience foam with different soundproof mats was tested. The mechanical properties and morphology of foam were observed and analyzed with microscope. The results show that the sound absorption coefficient of foam in low frequency region increases with the increase of thickness, but decreases in high frequency region. The sound absorption coefficient of foam increases with the increase of density. The foam performance of foam morphology has Significantly affected, the fine and uniform cell is conducive to the absorption of acoustic energy; different isocyanates due to differences in reactivity and structure, the foam also showed different sound absorption characteristics; high-pressure foam production of foam peak acoustic absorption frequency slightly higher Frequency shift, the composite ethylene - vinyl acetate copolymer elastomer (EVA) foam after the peak sound absorption frequency slightly to the low-frequency area.