Droplet-cluster transition in sheared polyamide 6–poly(styrene-ethylene-butadiene-styrene)–polypropylene ternary blends
writer:Yutian Zhu,Xiaodong Yang, Jinghua Yin, and Wei Jiang*
keywords:Droplet-cluster transitionin sheared;polyamide 6–poly(styrene-ethylene-butadiene-styrene)–polypropylene;ternary blends
source:期刊
Issue time:2010年
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.