本實驗分為兩部份，第一部分使用無乳化劑乳化聚合法合成出粒徑約為2μm之聚苯乙烯(Polystyrene，PS)微米粒子作為基材，並經由SQUID驗證本實驗以共沉澱法所製備出之四氧化三鐵(Fe3O4)奈米粒子具有超順磁性，且其飽和磁化量為68.1emu/g；接著以由低到高濃度的Fe3O4包覆於PS表面，提升其磁響應力，命名為PF1、PF2、PF3、PF4及PF5，由TGA分析PF5中Fe3O4的含量最高可達27.36 wt%。利用直流(DC)及交流(AC)磁場驅動PF1、PF2、PF3、PF4及PF5；另外，使用交流電場驅動PG1、PG2、PG3；誘導磁/電偶極矩的改變，產生磁/電場極化現象，使粒子彼此吸引而排列成串，造成穿透率的變化，進而呈現出不同的顯示效果。以光學顯微鏡(OM)證實粒子驅動成串的行為，並使用光譜儀量化穿透率的變化值，在低電壓(5Voltage)及低電流(2.5Ampere)的情況下驅動粒子成串；PF1的穿透率從施加磁場前的7%上升至16.8%、PF5的穿透率則可提升至39%；在交流磁場驅動試驗中，同樣可於低電壓(5Voltage)及低頻率(100Hz)下，使粒子產生磁極化進而吸引成粒子串，造成穿透率的上升，其中PF5的穿透率則可上升至42.36%，由此現象可以發現在交流磁場的變動下，可以減少直流磁場中可能導致粒子聚積於某一電極的現象，使穿透率略為上升。由此可製備出磁控顯示元件。
第二部份為將石墨片經由化學剝離法、表面改質及化學還原法等步驟，製備出正負兩種不同電性的還原氧化石墨烯(rGO-NH3+、rGO-COO-)，並逐層包覆於PS表面，藉以增加其電性響應力，即為PG1、PG2及PG3，同樣地以TGA分析PG3中rGO的含量最高可達29.75wt%。以光學顯微鏡(OM)證實粒子驅動成串的行為，並使用光譜儀量化穿透率的變化值，在交流電場的試驗中，PS介電粒子可於低電壓(5V)及低頻率(300Hz)下極化成串，且可藉由PS與石墨烯兩種複合材料的組成，使粒子得以在更短時間(5 seconds)及更低頻率(100Hz)時產生界面極化，並增強其極化程度，提高穿透率(PG3=64.8%)，進而達成不同的顯示效果，及其相關的顯示技術之應用。並可因此發現graphene與PS間介電常數及介電損耗值的差異性。

We used mulsifier-free emulsion polymerization to prepare 2μm polystyrene microspheres as a substrate. Sequentially, Fe3O4 nanoparticles possessing superparamagnetism with 68.1emu/g of saturation magnetization were immobilizes on the PS microspheres to operate magnetorheologically for display medium. The layer thicknesses of immobilized Fe3O4 nanoparticles on the surface of polystyrene were increased gradually to enhance the magnetic performance, denoted as PF1, PF2, PF3, PF4 and PF5. The contents of PF5 reached to 27.36 wt%, maximum Fe3O4 contents on the surface. We applied direct current and alternating current magnetic field to drive PF1, PF2, PF3, PF4 and PF5 in aqueous solutions into microspheres chains. We observed microspheres stringing behavior by optical microscope and spectrometer. Microsphere stringing behavior appeared along the magnetic field generated by DC (2.5A) at 5V. The top-view transmittance for PF1 and PF5 is increase from 7% to 16.8% and 39%, respectively. The microspheres stringing behavior also appeared along magnetic field generated by AC with 100Hz of frequency at 5V. The top-view transmittance for PF5 reached to 42.36% under this condition without precipitation.
In addition, two kinds of graphene oxide,(rGO-NH3+,rGO-COO-) were synthesized to immobilize on the surface of polystyrene by electrostastic force to improve the dielectric properties. Three various layer thicknesses of immobilized (rGO-NH3+/rGO-COO-) sheets on the surface of polystyrene from low to high were synthesized, denoted as PG1, PG2 and PG3. The contents of graphene for PG3 reached to 29.75 wt%. In the AC electric field experiment, polystyrene microspheres without graphene modification could form particle chain along the alternating electric field at 5V and 300Hz. Nevertheless, the polystyrene microspheres with graphene modification could be strung linearly at lower frequency (100Hz). In addition, response times (5s), polarizability and transmittance (PG3=64.8%) were also improved simultaneously.

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