液晶液滴與平板碰撞之行為研究

Liquid Crystal Droplet Hitting a Surface

張棋傑(Ci-Jie Jhang)

指導教授 ： 潘國隆

國立臺灣大學/工學院/機械工程學研究所/碩士(2022年)

https://doi.org/10.6342/NTU202203566

摘要

本研究以實驗的方式來探討液晶液滴撞擊平板之物理現象，並建立一套觀測設備，此設備可以用來拍攝並記錄在偏振光源的條件下，液晶液滴撞擊於表面完整的碰撞過程，藉由壓電式液滴產生器搭配訊號控制器與溫度控制器，準確地產生體積相同的液晶液滴，利用精密移動平台和轉動平台控制液滴落下之位置，液滴撞擊的玻璃載玻片使用丙酮、純水、乙醇、正丙醇、正庚醇、乙二醇、十二烷與十六烷各種溶液對表面進行處理，並運用不同的乾燥方式，包括氣槍吹拂、自然乾燥與烤箱烘烤。
實驗之重點在於觀察液晶液滴於各種表面的碰撞及擴展過程中，液晶分子與固體和液體之間的交互作用，而造成不同的液晶分子排列，藉由量測液滴的靜態接觸角來探討液晶液滴與各種表面之間的關係，玻璃載玻片表面若有溶液存在，則會使液晶液滴在碰撞後，液晶分子呈現平行排列，在完全乾燥的表面上則會呈現垂直排列。

關鍵字

液晶液滴碰撞 ； 偏振光 ； 按需滴墨 ； 接觸角 ； 表面處理

並列摘要

The study discusses the physical phenomenon of liquid crystal droplet hitting the surface was investigated experimentally, and a set of observation equipment was established. The piezoelectric droplet generator is combined with the signal controller and the temperature controller to accurately generate liquid crystal droplet with the same volume. The precise moving platform and the rotating platform are used to control the position where the droplets fall. The droplets hit the glass slide. Treat the surface with various solutions of acetone, pure water, ethanol, n-propanol, n-heptanol, ethylene glycol, dodecane and hexadecane, and use different drying methods, including air drying, natural drying and forced drying.
The focus of the experiment is to observe the interaction between liquid crystal molecules and solids during the collision and expansion of liquid crystal droplets on various surfaces, resulting in different arrangements of liquid crystal molecules, which are discussed by measuring the static contact angle of the droplets. To know the relationship between liquid crystal droplet and various surfaces. If there is a solution on the glass slide, the liquid crystal molecules will align parallel after the liquid crystal droplet hits the surface. The liquid crystal molecules align homeotropically to the surface on a completely dry surface.

並列關鍵字

Liquid crystal droplet collision ； Polarized light ； Drop-on-demand ； Contact angle ； Surface treatment

參考文獻

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