高分子安定藍相液晶之光電響應與配方之研究

Abstract

液晶的藍相介於各向同性及膽固醇相之間，有特殊的對稱性晶格結構，及亞毫秒等級的反應時間，然而傳統藍相液晶之溫度範圍約1~2K，應用上有其困難。藉由加入高分子單體並進行光聚合作用後，形成高分子聚合物網狀結構以穩定液晶的藍相結構，可大幅增加藍相的溫度範圍，此即為高分子安定藍相液晶；再藉由藍相液晶的克爾效應，可應用於顯示器上。 本論文主要對影響高分子安定藍相液晶的光電響應之幾項變因進行研究：1.改變高分子單體濃度，找出濃度對光電響應之關係；2.改變紫外光照射強度，找出照射強度對光電響應之關係；3.同在藍相下，不同量測溫度對光電響應之關係；4.外加電壓對光電響應之關係。另外對使用的不同液晶配方做其特性之分析。並綜合實驗結果找出達到最短反應時間之條件參數。

The blue phase is a liquid crystal phase between cholesteric phase and isotropic phase with spatially periodic crystal structure and sub-millisecond response time; however the usual narrow temperature range (1~2K) makes it difficult for application. By polymerizing a mixture of monomer, using UV illumination the polymer network could stabilize the blue phase structure called polymer-stabilized blue phase liquid crystal (PSBP). Besides, the Kerr effect of PSBP could be used in display technology. This research focuses on several factors affecting the opto-electric response: 1. the relationship between monomer concentrations of mixture recipes and opto-electric response; 2. the relationship between UV intensity while polymerizing and opto-electric response; 3. in blue phase, the relationship between operating temperature and opto-electric response; 4. The relationship between applied voltage and opto-electric response. In addition, by analyzing the feature of the used mixture recipe, we find out the best parameters to make response time shortest.