玻璃微珠/PI气凝胶复合材料的制备与吸声性能研究  

Preparation and Sound-absorbing Performance of Hollow Glass Microsphere/PI Aerogel Composites

作　　者：邵慧龙 费志方 李肖华 赵爽 李昆锋[1] 杨自春[1] SHAO Huilong;FEI Zhifang;LI Xiaohua;ZHAO Shuang;LI Kunfeng;YANG Zichun(School of Power Engineering,Naval University of Engineering,Wuhan 430033,China)

机构地区：[1]海军工程大学动力工程学院,武汉430033

出　　处：《材料导报》2023年第9期192-197,共6页Materials Reports

基　　金：国家自然科学基金(51802347)。

摘　　要：PI气凝胶是一种多孔吸声材料,但对中低频声波的吸声效果欠佳。为了提高PI气凝胶对中低频声波的吸声性能,引入不同粒径(29μm、40μm、55μm)的玻璃微珠(HGM)作为复合相,采用溶胶-凝胶、CO_(2)超临界干燥等工艺制备了中低频声波吸声性能良好的HGM/PI气凝胶复合材料,研究了复合材料的性质(比表面积、收缩率、密度)、微观结构以及吸声性能,分析了HGM的粒径、添加量和复合材料本身厚度对复合材料吸声性能的影响。结果表明:复合材料的密度(0.156~0.208 g/cm^(3))、比表面积(107.8~399.8 m^(2)/g)与HGM的堆叠密度和添加量有关。在500~6 300 Hz范围内,30 mm厚的空白样品(PI气凝胶)的吸声系数峰值为0.39(3 150 Hz),添加HGM后,相同厚度的复合材料在1 000~2 500 Hz出现峰值,较空白样品向低频方向移动,峰值大小为0.56~0.87,均高于0.39。对比发现,在1 000~2 500 Hz范围内,粒径为29μm的HGM与PI气凝胶复合后的材料吸声性能最好,粒径为40μm的HGM与PI气凝胶复合后的材料吸声性能最差。另外,随着HGM添加量的增加,复合材料的吸声系数峰值逐渐向低频方向移动,且出现先减小后增大的趋势,同时吸声系数峰值随着材料厚度的减小向高频方向移动。As a porous sound-absorbing material,PI aerogel has a poor sound-absorbing performance for low-and medium-frequency sound waves.In order to improve the sound-absorbing performance of PI aerogel to sound waves with low or medium frequency,the present study introduced hollow glass microsphere(HGM) with different particle sizes(29 μm,40 μm and 55 μm) as a component to prepare HGM/PI aerogel composites with excellent low-and medium-frequency sound-absorbing performance by sol-gel and supercritical CO_(2) drying.In this work,the properties(specific surface area,shrinkage and density),microstructure and sound-absorbing performance of the composites were studied,and the effects of particle size and added amount of HGM,and thickness of the composites on the sound-absorbing performance of the composites were analyzed.The results indicate that the density(0.156-0.208 g/cm^(3)) and specific surface area(107.8-399.8 m^(2)/g) of the composites are rela-ted to the stacking density and the added amount of HGM.In the range of 500-6 300 Hz,the peak value of sound-absorbing coefficient of blank sample(PI aerogel) with a thickness of 30 mm is 0.39,corresponding to 3 150 Hz.After introducing HGM component,the composites with the same thickness have peak values within the range of 1 000-2 500 Hz.The positions of peak values shift to the lower-frequency band compared with blank sample and the values are higher than 0.39,ranging from 0.56 to 0.87.According to the comparison of composites composed of HGM with different particle sizes,in the range of 1 000-2 500 Hz,the composite material composed of 29 μm HGM and PI aerogel has the best sound-absorbing performance,while the composite material composed of 40 μm HGM and PI aerogel has the worst sound-absorbing performance.In addition,with the increase of the amount of HGM,the peak value of the sound-absorbing coefficient of the composite material gradually shifts to the lower frequency band,and appears to decrease at first and then increase,and the peak value of the sound-absorbing co

关 键 词：空心玻璃微珠 PI气凝胶 复合材料 吸声性能 

分 类 号：TB332[一般工业技术—材料科学与工程]