研究奈米粒子在液晶盒聚集特性之動態光散射儀

Abstract

動態光散射儀對於研究溶液中的微粒是一個強大且非侵入式的技術，若再搭配去偏振動態光散射系統，則可以同時量測到平移與旋轉擴散係數(Rotational and Translational diffusion coefficients)，了解粒子在三維維度下的運動狀態與過程，進而得到粒子形狀與大小。本論文架設一套動態光散射儀與去偏振態動態光散射儀系統，利用已知粒徑的聚苯乙烯球進行動態光散射儀系統的測試及校正與演算法的驗證，最後利用此系統的非破壞式量測優點，初步應用於分析二氧化矽奈米粒子摻雜於液晶盒中的聚集特性。

The dynamic light scattering (DLS) spectroscopy is a powerful and non-invasive technique for the study of optical isotropic particles dispersed in solution. In a suspension of optical anisotropic particles, a depolarized dynamic light scattering (DDLS) spectroscopy is required for measuring different polarization of scattering light, in which cases the detected signal depends on the translational diffusion and the rotational diffusion coefficients. In this work, we have developed a system consisting of DLS and DDLS spectroscopy. The optical system and the algorithm of data analysis were characterized by using the standard polystyrene particles. Finally, we have applied this system to study the aggregation of silica nanoparticles doped in liquid crystal cells.