Zhang Xianwei, Ma Zhongzhu, Fan Hong, Bittencourt Carla, Wan Jintao, Dubois Philippe
State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China.
Center of Innovation and Research in Materials and Polymers (CIRMAP), University of Mons, Place du Parc 23, B-7000 Mons, Belgium.
Beilstein J Nanotechnol. 2018 Dec 19;9:3053-3068. doi: 10.3762/bjnano.9.284. eCollection 2018.
A novel layered double hydroxide modified by octa-substituted carboxy-terminated polyhedral oligomeric silsesquioxane was prepared via a one-step method and characterized by Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, elemental analysis, thermogravimetric analysis, and microscale combustion calorimetry (MCC). Results showed that the silsesquioxane modified-LDH (OLDH) revealed an increase in the interlayer distance, nanoscale plate-like morphology of primary particles, and improved thermal stability. A synergistic effect between the siloxane moiety and Mg-Al hydroxide was found during thermal degradation, and confirmed by the study of degradation kinetics together with the analysis of the surface morphologies and elemental components of char residues. Moreover, in contrast to conventional organic modified LDH (e.g., dodecylbenzenesulfonate-LDH), the MCC results showed a significant decrease in the heat release rate and total heat release, indicating the low flammability of OLDH.
通过一步法制备了一种由八取代羧基封端的多面体低聚倍半硅氧烷改性的新型层状双氢氧化物，并通过傅里叶变换红外光谱、X射线光电子能谱、X射线衍射、透射电子显微镜、扫描电子显微镜、元素分析、热重分析和微尺度燃烧量热法（MCC）对其进行了表征。结果表明，倍半硅氧烷改性层状双氢氧化物（OLDH）的层间距增大，初级颗粒呈现纳米级片状形态，热稳定性提高。在热降解过程中发现硅氧烷部分与Mg-Al氢氧化物之间存在协同效应，通过降解动力学研究以及对残炭表面形态和元素组成的分析得到了证实。此外，与传统的有机改性层状双氢氧化物（如十二烷基苯磺酸盐-LDH）相比，MCC结果表明热释放速率和总热释放显著降低，表明OLDH的可燃性较低。
