Thermal characterization of a montmorillonite, modified with polyethylene-glycols (PEG1500 and PEG4000), by in situ HT-XRD and FT IR: Formation of a high-temperature phase
Thermal characterization of a montmorillonite, modified with polyethylene-glycols (PEG1500 and PEG4000), by in situ HT-XRD and FT IR: Formation of a high-temperature phase
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DOI：
10.1016/j.clay.2012.02.015
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发表时间：
2012-05
影响因子：
5.6
通讯作者：
L. Zampori;G. Dotelli;P. G. Stampino;C. Cristiani;F. Zorzi;E. Finocchio
中科院分区：
文献类型：
--
作者：
L. Zampori;G. Dotelli;P. G. Stampino;C. Cristiani;F. Zorzi;E. Finocchio
将两种具有不同分子量的聚乙二醇（PEG）（即 PEG 1500 和 PEG 4000）嵌入 STx 蒙脱土的层间空间内。通过热重分析 (TG) 和原位高温 XRD 研究了插层粘土矿物的微观结构，以评估层间空间随温度的变化。 TG 和热 XRD 数据分别在 25–1000°C 和 25–850°C 的温度范围内收集。通过热重和红外光谱检测发现，插层聚合物的分解与纯表面活性剂的分解非常不同。原位高温 XRD 数据显示在 250°C 下检测到高温相的形成，与嵌入的 PEG 的分子量无关。当温度降低至 25°C 并再次升高至 250°C 时，该相表现出稳定。当改性粘土矿物在 200°C 下加热时，观察到不规则的层间相。
Two polyethylene-glycols (PEG), having different molecular weight (i.e. PEG 1500 and PEG 4000) were intercalated inside the interlayer space of a STx montmorillonite. The microstructure of the intercalated clay mineral was investigated by thermogravimetry (TG) and in situ high temperature-XRD, in order to assess the evolution of the interlayer space upon temperature. Data were collected over a temperature range of 25–1000°C and 25–850°C for TG and thermo-XRD, respectively. Decomposition of the intercalated polymers was very different compared to the one of the pure surfactants, as detected by TG and FT IR spectroscopy. In situ high temperature-XRD data showed the formation of a high-temperature phase, detected at 250°C, independently from the molecular weight of the PEG intercalated. This phase showed to be stable when the temperature was decreased to 25°C and was raised again to 250°C. An irregularly interstratified phase was observed when the modified clay minerals were heated at 200°C.