Mixture design applied to the rheology of clay gel mixtures
Mixture design applied to the rheology of clay gel mixtures
复制标题
DOI：
10.1007/s00397-022-01366-9
复制
发表时间：
2022-08-18
期刊：
影响因子：
2.3
通讯作者：
Aarts, Dirk G. A. L.
中科院分区：
文献类型：
--
作者：
Boulet, Camille C. S.;Brown, Alan;Aarts, Dirk G. A. L.
我们使用混合物设计来预测Laponite EP和膨润土粘土的混合物的流变参数，即储能模量和损耗模量G'和G”以及临界应力σ（c）。合成锂皂石EP是一种有机涂层合成锂皂石，与其未改性形式相比，显示出不寻常的流变行为。我们研究了盐（氯化镁）和表面活性剂（吐温20）在4和9之间改变pH值的影响。我们发现可靠的复杂模型与显着的高阶项表明，凝胶的流变行为是不是每个单一的化合物的功能，而是多个相互作用的结果。这种相互作用对G'和G”具有拮抗作用。较强的凝胶被发现在低浓度的氯化镁和吐温20。响应于应力的凝胶稳定性随着吐温20的量而增加，但随着氯化镁而降低。这种不同的行为可能是血小板电荷和不同组分之间相互作用的结果，以及盐溶效应与盐析效应。我们确定了G'值适用于农业化学产品的条件。这里介绍的方法是一种快速可靠的方法来配制具有目标流变性能的产品。
We used mixture design to predict rheological parameters, namely the storage and loss modulus G' and G" and the critical stress sigma(c), of mixtures of Laponite EP and bentonite clay. Laponite EP is an organically coated laponite displaying unusual rheological behaviour compared to its unmodified form. We examined the effect of salt (magnesium chloride) and of surfactant (Tween 20) varying the pH between 4 and 9. We found reliable complex models with significant higher order terms showing that the rheological behaviour of the gels was not a function of each single compound, but instead the result of multiple interactions. Such interactions had an antagonistic effect on G' and G". Stronger gels were found at low concentrations of magnesium chloride and Tween 20. The gel stability in response to stress increased with the amount of Tween 20, but decreased with magnesium chloride. Such distinct behaviour may be the result of interactions between the platelet charges and the different components, as well as salting in versus salting out effects. We identified the conditions for which the values of G' were suitable for agrochemical products. The method presented here is a quick and reliable approach to formulate products with targeted rheological properties.