Abstract Novel ultralight porous fiber-based composites are a very attractive subject in the material chemistry and are enabled to promise applications in the sound absorption fields. In this work, it reported a facile strategy to prepare the flame-retardant, sound-absorbing, and mechanical enhancement porous fiber-based composites (PFC-EM-x) by using natural cellulose fiber, glass fiber, and flame retardant. Subsequently, the expandable microspheres (EMs) were added to construct the well-defined porous microstructure of materials for the enhancement in sound-absorbing performance. The results demonstrated that the high EMs contents had a remarkable influence on the porous structure of the composites so that the composites achieved the outstanding sound-absorbing performance and acceptable mechanical properties compared with other reported materials, especially as-prepared PFC-EM-20 composite showed excellent sound absorption at a range of high frequencies with the maximum sound absorption coefficient of 0.781 and tensile strength of 1.07 kN/m. Moreover, the limiting oxygen index values of all the samples were more than 26, both V1 and V2 rating in UL-94 test were achieved, which indicated that the obtained PFC-EM-x composites displayed outstanding flame retardancy. In summary, this study provides a facile strategy to rationally construct mechanically robust, highly efficient sound-absorbing and flame retardant ultralight composites which have promising applications in the future as green engineering materials. Graphical Abstract

中文翻译：

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具有优异吸音和阻燃性能的新型多孔纤维基复合材料

摘要 新型超轻多孔纤维基复合材料是材料化学中一个非常有吸引力的课题，有望在吸声领域得到应用。在这项工作中，它报告了一种使用天然纤维素纤维、玻璃纤维和阻燃剂制备阻燃、吸音和机械增强多孔纤维基复合材料 (PFC-EM-x) 的简便策略。随后，添加可膨胀微球 (EM) 以构建材料的明确多孔微结构，以提高吸音性能。结果表明，高 EMs 含量对复合材料的多孔结构有显着影响，因此与其他报道的材料相比，尤其是制备的 PFC-EM-20 复合材料，复合材料具有出色的吸声性能和可接受的机械性能在高频范围内表现出优异的吸声性能，最大吸声系数为 0.781，抗拉强度为 1.07 kN/m。此外，所有样品的极限氧指数值均大于26，达到了UL-94测试中的V1和V2等级，这表明所获得的PFC-EM-x复合材料显示出优异的阻燃性。总之，这项研究提供了一种简单的策略来合理地构建机械稳健，高效吸音阻燃超轻复合材料作为绿色工程材料在未来具有广阔的应用前景。图形概要