Shear-induced anisotropic microstructure in phase-separated biopolymer mixtures
Shear-induced anisotropic microstructure in phase-separated biopolymer mixtures
复制标题
相分离生物聚合物混合物中剪切诱导的各向异性微观结构
DOI：
10.1016/s0268-005x(99)00062-4
复制
发表时间：
2000
影响因子：
10.7
通讯作者：
I. Norton
中科院分区：
文献类型：
--
作者：
B. Wolf;R. Scirocco;W. Frith;I. Norton
这项工作涉及的形成，在流动下，规则的，各向异性的颗粒形状的相分离的液-液生物聚合物混合物（水包水乳液）和固定这样的结构，通过凝胶化的一个或两个阶段。假设为了流动加工的目的，这种水包水乳液可以以与常规乳液相同的方式处理，则选择剪切流动工艺。通过该途径产生的微结构显示出宽范围的形状，从在剪切应力范围的下端处形成的球形颗粒到在较高剪切应力下形成的长延伸颗粒以及不规则形状的颗粒。这些不同的微观结构开发的背景下，粘度和剪切速率的结构化过程中记录的数据进行了讨论。对于其中一种混合物，定量了两相之间的粘度比和界面张力。结果发现，在这种混合物中观察到的颗粒变形符合液滴变形理论的预测。
This work is concerned with the formation, under flow, of regular, anisotropic particle shapes in phase separated liquid–liquid biopolymer mixtures (water-in-water emulsions) and the fixing of such structures through gelation of one or both phases. Hypothesising that, for the purpose of flow processing, such water-in-water emulsions can be treated in the same manner as conventional emulsions, a shear flow process was chosen. Microstructures produced by this route show a wide spectrum of shape, from spherical particles, developed at the lower end of the shear stress range, to long extended particles, as well as irregularly shaped particles, formed at higher shear stresses. These different microstructures developed are discussed in the context of viscosity and shear rate data recorded during the structuring process. For one of the mixtures, the viscosity ratio and interfacial tension between the two phases were quantified. It was found that the observed particle deformations in this mixture coincided with predictions from droplet deformation theories.