在過去的液晶科學研究中，在液晶中摻雜奈米粒子或是膠體粒子的研究及液晶中粒子跟粒子之間的交互作用是個熱門的主題，液晶擁有天生的異向性特質，對奈米粒子和膠體粒子來說，很難均勻分散在液晶中，因為液晶連續彈性體理論和延伸拓樸缺陷導致的拓樸電荷，使得膠體粒子無法均勻混入液晶，甚至膠體粒子會互相聚集，然而，中孔洞氧化矽空心球的發明卻是能解決顆粒聚集的問題，除此之外，也能延伸製作出散射型的元件。
這篇論文主要是探討在氧化矽空心球周圍液晶分子的排列方式，並且提出模型描述氧化矽空心球在液晶中的行為，用實驗去驗證我們的模型，實驗上從偏光顯微鏡去觀(POM)察比較氧化矽空心球和膠體粒子在液晶中的不同樣貌並且用相機記錄下來，施加電場去觀察氧化矽空心球和膠體粒子樣貌的演化，之後使用Matlab軟體去分析POM，繪製出亮度隨著距離粒子中點的關係，也用Matlab軟體去處理加強相片，使得相片可以充分表現出散射和液晶排列的行為。我們還通過光鉗實驗去拉動膠體粒子，確定中孔洞氧化矽空心球在液晶中無法輕易地移動即使雷射強度足夠到使向列型液晶相變。基於以上實驗與分析結果，中孔洞氧化矽空心球的表面因為混亂分佈孔洞會形成局部穩定亂序的液晶，由於很強的無序力使得此區域無法適用連續彈性體的定義。因此，中孔洞氧化矽空心球在液晶中將會在球殼內外產生散射的日冕(scattering corona)，此無序態在差示掃描量熱法分析得到證實。在中孔洞氧化矽空心球日冕周遭的液晶如同感受的錨定力趨近於零的邊界條件，無法形成拓樸缺陷（拓樸電荷）及連續彈性體的反彈力。如此一來中孔洞氧化矽空心球便不會聚集在液晶中。

Doping nano-particles or colloidal particles in liquid crystals (LCs) and interaction between particles in LCs have been reported for decades. Nano-particles and colloidal particles inhomogeneously disperse in LCs are resulted from the anisotropic property of LC. Due to the elastic continuum theory and extended topological defects induced topological charges, colloidal particles can not well disperse in LCs and further aggregate. However, the invention of mesoporous silica hollow spheres (MPSHSs) could resolve the problem of particles aggregation and improve further scattering device.
In this thesis, we propose the arrangement of LCs molecules around MPSHSs and model for the behavior of MPSHSs in LCs. We observe the variation of the MPSHSs and colloidal particles in LCs by applying electric field under polarized optical microscopy (POM). We use Matlab to analysis the POM brightness and plot the brightness variation with distance. We drove colloidal particles by optical tweezer, but MPSHSs are hard to move in LCs even if the laser power is high to induce nematic LC phase transition. The surface of MPSHS is relatively rough and the quenched disordered force caused by porous surface of MPSHSs is quite random so there is a scattering corona around the MPSHS shell which can not be defined by elastic continuum theory. This disorder scattering corona phase is proved by Differential scanning calorimetry (DSC) experiment. As the long-range quasi-anchoring on boundary of corona is close to zero, topological defects and distorted elastic force can notbe induced. Therefore, MPSHS well disperses in LC homogeneously.

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