本研究利用耗散粒子動力學方法，模擬棒狀奈米顆粒/雙嵌段共聚物之共混系統在流場中的相態變化。我們研究的目的在於了解非等向性的棒狀奈米顆粒(nanorod)如何影響雙嵌段共聚物共混系統的自組裝結構，並且了解流場如何影響此系統的動力學行為。探討的變因主要有兩個：1. 棒狀奈米顆粒的濃度2. 棒狀奈米顆粒的長度。最後，我們比較不同系統的流變性質，如黏度(viscosity)等，以及觀察棒狀奈米顆粒在系統中的排向性(orientation)。
在本研究發現，添加雙親性棒狀奈米顆粒於雙嵌段共聚物中，能夠使這個結構更加穩固，減少此共混系統的彎曲擾動現象，因此雙親性棒狀奈米顆粒在較高濃度下，觀察不到垂直層板結構。此外，在改變長度這個變因下，研究發現長度太長時，會因為奈米顆粒在空間的排斥下，導致其在層板間的排序較亂，也降低了此共混系統的黏度。在這個研究中，我們提供了方法來創造實用性材料，並且提升其加工性質。

The microphase transitions of a nanorod/diblock copolymer composite under steady shear flow are investigated via dissipative particle dynamics. The aim of our study is to understand how the anisotropic nanorods affect the structure of diblock copolymer melts and how the shear flow induces the dynamic behaviors of the composites. We investigate two effects: one is nanorods concentration, and the other is nanorods length. Finally, we compare the rheological properties of different conditions and observe the oriention of nanorods. Our results show that Janus nanorods can not only reinforce the material, but also reduce fluctuation of the structure. Therefore, we can’t observe perpendicular lamellae at high nanorods concentrations. Additionally, we also observe that nanorods with longer length will be more disorder owing to the repellence between the nanorods and thus decrease the viscosity of the composites. In this research, we provide a viable approach to create functional materials with enhance processing properties.

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