探討聚苯乙烯微米球摻混向列型液晶之電流變效應

Blend polystyrene microspheres of nematic liquid crystal ER effect

陳宥龍(Yu-Long Chen)

指導教授 ： 芮祥鵬

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2011年)

摘要

本研究主要是製作一球型微米粒徑的聚苯乙烯，利用分散聚合法製作出均勻的3μm微米球，來當做為固相粒子，將此聚苯乙烯微米球摻入各種不同的向列型液晶中製成一均相的電流變液體，除此之外還合成了聚苯乙烯與聚苯乙烯磺酸鈉之共聚物，看是否會對電流變效應有所提升。以偏光顯微鏡來觀察向列型液晶是否因為加入聚苯乙烯微米球後造成其形成液晶相的溫度有所變化，並在偏光顯微鏡下加入電場看微米球是否因電場的加入後有所變化或移動。使用平板式流變儀(Physica MCR 301)，將我們做的電流變液放入兩平板間，並施加電場其結果發現，當電場施加的越大其黏度會因電場強度越大而逐步攀升。同時我們也做了純的向列型液晶電流變測試，其效果並沒有加入微米球的電流變液來的理想，此說明了聚苯乙烯微米粒子在向列型液晶中被膨潤並且其中的三維結構因電場提升而更為緊密，或是因液晶小分子在各個微米球上產生的錨定效應造成球與球之間牽引力上升，使得黏度上升。

關鍵字

液晶分子 ； 液晶電流變 ； 聚苯乙烯

並列摘要

This study is the production of a micron diameter spherical polystyrene polymer was prepared by dispersing microspheres create uniform 3μm to as the solid phase particles, this incorporation of polystyrene microspheres of different nematic liquid crystals made of a homogeneous ER fluid, in addition to synthesis of the copolymer of polystyrene and polystyrene sulfonate, to see if the ER effect will be improved. The polarizing microscope to observe the nematic liquid crystal is the addition of polystyrene microspheres caused by the formation of liquid phase after the temperature change, and joined the field in the polarized light microscope to see it because of microspheres are subject to change after the addition of the electric field or move. Use plate rheometer (Physica MCR 301), the ER we do put between two plates, and applied electric field it was found that the greater when the electric field applied electric field strength due to its higher viscosity gradually rising. We also made a pure nematic liquid crystal ER test, the effect of adding microspheres did not change the current solution to the ideal, this illustrates the PS-micron particles in nematic liquid crystal, and was one of the three-dimensional swelling improve the structure of the electric field more closely by, or due to liquid crystal molecules in various microspheres produced anchoring effect on the result increased traction between the ball and the ball, making the viscosity increase.

並列關鍵字

Liquid crystal ； liquid crystal ER ； Polystyrene

參考文獻

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