Polyvinyl alcohol (PVA) hydrogels were prepared by a cyclic freezing–thawing technique without any cross-linker agent, using PVA and Maghnite water dispersion with different ratios. The obtained results have shown a higher thermal stability of samples with sodium than with alkylammonium Maghnite. Furthermore, thermal stability was maximum at the lowest investigated Maghnite/PVA ratio, but higher than for the pure PVA at all the investigated compositions. DSC analysis has shown both a low crystal degree and a low heat capacity jump at the glass transition temperature for samples with high Maghnite content. This phase does not seem to depend on the kind of cations, sodium or alkylammonium into the gallery of the clay.

中文翻译：

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通过 DSC 和 TGA 分析具有有机和钠 MMT 的 PVA 水凝胶的热表征

聚乙烯醇（PVA）水凝胶是通过循环冻融技术制备的，没有任何交联剂，使用不同比例的 PVA 和 Maghnite 水分散体。所得结果表明，含钠的样品比含烷基铵镁铁矿的样品具有更高的热稳定性。此外，热稳定性在最低研究的 Maghnite/PVA 比率下最大，但在所有研究的成分中都高于纯 PVA。DSC 分析表明，镁铁矿含量高的样品在玻璃化转变温度下具有低结晶度和低热容跳跃。这个阶段似乎并不取决于进入粘土通道的阳离子、钠或烷基铵的种类。