Zhu Yutian, Yang Xiaodong, Yin Jinghua, Jiang Wei
State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People's Republic of China.
Phys Rev E Stat Nonlin Soft Matter Phys. 2010 Sep;82(3 Pt 1):031807. doi: 10.1103/PhysRevE.82.031807. Epub 2010 Sep 30.
We have used a Linkam CSS 450 stage equipped with an optical microscope to study online the evolution of the morphology and structure of polyamide 6 (PA6)-poly(styrene-ethylene-butadiene-styrene) (SEBS)-polypropylene (PP) ternary blends under shear flow. At a high shear rate (60 s(-1)), large drops of PA6 and SEBS broke up to form small randomly distributed PA6 droplets covered by SEBS in the PP matrix. These droplets aggregated into a well-ordered structure, i.e., parallel clusters, after decreasing the shear rate abruptly to within the range of 1.5-3.5 s(-1). Interestingly, these parallel clusters were aligned perpendicular to the direction of shear flow. An important feature of these parallel clusters is that they can be maintained for a long period of time (several tens of minutes) at the given shear rate or after cessation of flow; this feature allows us to freeze the structure by decreasing the temperature.
我们使用配备了光学显微镜的Linkam CSS 450载物台在线研究了聚酰胺6（PA6）-聚（苯乙烯-乙烯-丁二烯-苯乙烯）（SEBS）-聚丙烯（PP）三元共混物在剪切流动下的形态和结构演变。在高剪切速率（60 s⁻¹）下，PA6和SEBS的大液滴破裂，形成在PP基体中随机分布的、被SEBS覆盖的小PA6液滴。在将剪切速率突然降至1.5 - 3.5 s⁻¹范围内后，这些液滴聚集成一种有序结构，即平行簇。有趣的是，这些平行簇垂直于剪切流动方向排列。这些平行簇的一个重要特征是，它们在给定的剪切速率下或流动停止后能够长时间（几十分钟）保持；这一特性使我们能够通过降低温度来冻结结构。
