液晶摻雜二氧化矽奈米粒子之相分離機制研究

Abstract

本研究在向列型液晶盒中摻雜二氧化矽奈米粒子，加熱樣品至超過液晶澄清點溫度後開始降溫，在降溫過程中，使用光學顯微鏡觀察液晶與二氧化矽奈米粒子相分離的過程，並且以電容電感阻抗分析儀量測樣品的介電頻譜。我們發現降溫過程中液晶的相態轉變和二氧化矽粒子的團聚現象與二氧化矽奈米粒子的表面特性有關，而且該相態轉變和團聚現象會呈現在介電頻譜的變化上。

This work discusses the phase separation of silica nanoparticle-doped liquid crystal (LC) mixtures. We find that the phase separation of the LC mixtures involves the nucleation and growth of nematic domains followed by the aggregation of silica nanoparticles. The final morphology of LC mixtures after phase separation depends on the concentration and surface properties of silica nanoparticles. The temperature-dependent dielectric permittivity at 1 kHz and 10 Hz can reveal the clear point temperature and the onset of the aggregation of silica nanoparticles in LC mixtures, respectively.