Department of Physical Chemistry II, Technische Universität Dortmund, 44227 Dortmund, Otto-Hahn-Straße 6, Germany.
Phys Chem Chem Phys. 2011 Feb 21;13(7):2765-73. doi: 10.1039/c0cp01803a. Epub 2010 Dec 10.
This paper describes the mechanical properties of thin-walled, liquid-filled composite capsules consisting of calcium pectinate and shellac. In a series of experiments we measured the deformation of these particles in a spinning drop apparatus. For different pH-values we studied the elastic properties of these particles and compared the obtained results with the mechanical response measured by squeezing capsule experiments. In analogy to these experiments, we also investigated liquid-filled unloaded calcium pectinate capsules without the addition of shellac. The deformation properties of these experiments and the surface Young moduli were in good agreement. Furthermore we investigated the liquid-filled calcium pectinate and the composite capsules by NMR microscopy. These experiments allowed investigations of the membrane thickness and the kinetics of membrane growing. Additional characterizations by stress controlled small amplitude surface shear experiments of similar composed gel layers provided coherent results for the surface Young modulus.
本文描述了由果胶酸钙和紫胶组成的薄壁、充液复合胶囊的力学性能。在一系列实验中，我们在旋转液滴装置中测量了这些粒子的变形。针对不同的 pH 值，我们研究了这些粒子的弹性性质，并将得到的结果与通过挤压胶囊实验测量的机械响应进行了比较。类似这些实验，我们还研究了没有添加紫胶的充液未加载果胶酸钙胶囊。这些实验的变形性质和表面杨氏模量吻合较好。此外，我们还通过 NMR 显微镜研究了充液果胶酸钙和复合胶囊。这些实验允许研究膜厚度和膜生长动力学。通过对类似组成的凝胶层进行应力控制的小振幅表面剪切实验的附加特性分析，为表面杨氏模量提供了一致的结果。
