Chen Chunping, Ruengkajorn Kanittika, Buffet Jean-Charles, O'Hare Dermot
Chemistry Research Laboratory, Department of Chemistry, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
RSC Adv. 2018 Oct 9;8(60):34650-34655. doi: 10.1039/c8ra06822d. eCollection 2018 Oct 4.
Understanding the water adsorbancy of highly dispersed, high surface area layered double hydroxide (LDH) is of great importance as it directly relates to their hydrophobicity and subsequent use as additives in LDH-polymer nanocomposites. In this study, we have investigated the water vapour uptake response of highly dispersed, high surface area aqueous miscible organic-LDHs (AMO-LDHs) in two relative humidity atmospheres (RH99 and RH60) at 20 °C. We observed that AMO-MgAl-CO and AMO-ZnMgAl-CO exhibited very high water vapour uptake in an RH99 atmosphere at 20 °C (56 wt% and 20 wt% for MgAl-CO and ZnMgAl-CO LDH respectively after 120 h). The crystallinity in both -plane and -axis of the LDHs increased with increasing exposure uptake. The water vapour adsorption capacity of the AMO-LDHs can be dramatically reduced by treatment with stearic acid.
了解高度分散、高比表面积层状双氢氧化物（LDH）的吸水性非常重要，因为这直接关系到它们的疏水性以及随后作为LDH-聚合物纳米复合材料添加剂的用途。在本研究中，我们研究了高度分散、高比表面积的水溶性有机-LDHs（AMO-LDHs）在20°C的两种相对湿度环境（RH99和RH60）中的水蒸气吸收响应。我们观察到，AMO-MgAl-CO和AMO-ZnMgAl-CO在20°C的RH99环境中表现出非常高的水蒸气吸收（120小时后，MgAl-CO和ZnMgAl-CO LDH分别为56 wt%和20 wt%）。随着暴露吸收量的增加，LDHs在平面和轴向上的结晶度都增加。用硬脂酸处理可以显著降低AMO-LDHs的水蒸气吸附能力。
