Department of Physics, Lomonosov Moscow State University, 119991 Moscow, Russia.
Department of Physics, Lomonosov Moscow State University, 119991 Moscow, Russia.
Carbohydr Polym. 2022 Apr 15;282:119106. doi: 10.1016/j.carbpol.2022.119106. Epub 2022 Jan 10.
Alginate hydrogels with embedded rigid percolating network of halloysite clay nanotubes were evaluated as a novel ink for 3D printing. Hydrophilic alginate macromolecules adsorbing on halloysite stabilize the network of the nanotubes and form their own network of interlaced polymer chains. The effect of halloysite content on the structure and properties of the hydrogels was studied by rheometry, thermogravimetric analysis, FTIR-spectroscopy, dynamic light scattering, transmission electron microscopy, and 3D cryo-electron microscopy. Hydrogels demonstrate a very pronounced shear-thinning at extrusion and rather quick viscosity recovery after extrusion assigned to rapid rearrangement of the network structure promoted by mobile alginate chains. Even at low volume fractions (up to 0.054) the nanotubes reinforce the hydrogel increasing its storage modulus up to 650 Pa and inducing the appearance of yield stress. These properties make the alginate/halloysite hydrogels promising for the application in 3D printing for fabrication of green and sustainable nanocomposite materials made from natural components.
研究了具有嵌入海泡石纳米管刚性渗透网络的海藻酸盐水凝胶，将其作为一种新型的 3D 打印墨水。吸附在海泡石上的亲水性海藻酸盐大分子稳定了纳米管的网络，并形成了相互交织的聚合物链的自身网络。通过流变学、热重分析、FTIR 光谱、动态光散射、透射电子显微镜和 3D 冷冻电子显微镜研究了海泡石含量对水凝胶结构和性能的影响。水凝胶在挤出时表现出非常明显的剪切变稀，并且在挤出后具有相当快的粘度恢复，这归因于可移动海藻酸盐链促进的网络结构的快速重排。即使在低体积分数（高达 0.054）下，纳米管也能增强水凝胶，使其储能模量增加到 650 Pa，并诱导屈服应力的出现。这些特性使得海藻酸盐/海泡石水凝胶有望应用于 3D 打印，用于制造由天然成分制成的绿色可持续纳米复合材料。
