Ji Wenfei, Zhang Qicheng, van Duijneveldt Jeroen S, Briscoe Wuge H, Scarpa Fabrizio
School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K.
Bristol Composites Institute, University of Bristol, University Walk, Bristol BS8 1TR, U.K.
ACS Appl Polym Mater. 2024 Aug 22;6(17):10322-10333. doi: 10.1021/acsapm.4c01437. eCollection 2024 Sep 13.
In this work, a flexible polyurethane (PU) foam/polymer/clay (PUF/PAASep) composite is prepared via a simple dip-coating method. The composite exhibits excellent damping properties under quasi-static compression, vibration transmissibility, and impact resistance. For the composite preparation, sepiolite (Sep) dispersion in a polyacrylic acid (PAA) solution is first homogenized and evaluated using microscopy, and the obtained PAASep suspension is used to coat the PU foam uniformly for optimization of the quasi-static mechanical performance of the foam composites. The PU foam struts coated with 1 wt % PAA and 3 wt % sepiolite are strengthened, resulting in an 8-fold improvement of the stiffness and three-times increase of the impact force resistance compared to the uncoated PU foams. More importantly, the PU foam composites show a remarkable vibration damping capability, with the loss modulus 57 times that of the uncoated PU foams, enabled by micro friction and stick-slip effects mediated by the PAASep coatings. The facile prepared PAASep-coated PU foams have significant potential for cushioning, packaging, and broad engineering applications involving energy absorption.
在本工作中，通过一种简单的浸涂方法制备了一种柔性聚氨酯（PU）泡沫/聚合物/粘土（PUF/PAASep）复合材料。该复合材料在准静态压缩、振动传递和抗冲击方面表现出优异的阻尼性能。对于复合材料的制备，首先将海泡石（Sep）分散在聚丙烯酸（PAA）溶液中，通过显微镜进行均匀化和评估，然后将得到的PAASep悬浮液均匀地涂覆在PU泡沫上，以优化泡沫复合材料的准静态力学性能。涂覆有1 wt% PAA和3 wt%海泡石的PU泡沫支柱得到了增强，与未涂覆的PU泡沫相比，刚度提高了8倍，抗冲击力增加了3倍。更重要的是，PU泡沫复合材料表现出显著的减振能力，损耗模量是未涂覆PU泡沫的57倍，这是由PAASep涂层介导的微摩擦和粘滑效应实现的。这种通过简便方法制备的PAASep涂覆的PU泡沫在缓冲、包装以及涉及能量吸收的广泛工程应用中具有巨大潜力。
