【摘要】：纖維素作為地球上儲量最豐富的可再生資源,對其開發(fā)和應(yīng)用越來越被重視。已經(jīng)工業(yè)化的纖維素纖維有粘膠纖維和Lyocell纖維,但是其紡制過程中存在環(huán)境污染、能耗大等問題。離子液體,作為新型溶劑,對纖維素有很強的的溶解能力,纖維素/離子液體體系制備纖維素纖維有環(huán)保及溶劑易回收等優(yōu)點,但是纖維素濃度增大會導致纖維素溶液體系粘度急劇增大,為了制備"高濃低粘"的纖維素溶液,纖維素液晶體系被提出。本研究設(shè)計并合成了新型纖維素側(cè)鏈液晶基元,研究了形成側(cè)鏈液晶的條件,制備了側(cè)鏈型纖維素液晶,并研究其流變性和液晶性,并且利用干濕法紡絲制備了纖維素纖維,具體研究內(nèi)容如下:利用濁度測試和紅外研究了液晶基元在離子液體中的溶解度及相互作用力,研究表明,常溫時,液晶基元在離子液體中的溶解度為5.78 wt%,液晶基元和離子液體之間只通過物理力結(jié)合而不發(fā)生化學反應(yīng)。采用穩(wěn)態(tài)和動態(tài)流變測試、偏光顯微鏡、差示掃描量熱儀和小角X衍射儀來研究纖維素/液晶基元/離子液體體系的相行為和流變行為。結(jié)果表明,當纖維素的濃度是6 wt%時,形成纖維素液晶溶液所需液晶基元的臨界濃度是2-4wt%,臨界溫度是40-80℃,形成的晶態(tài)結(jié)構(gòu)是近晶相。COX-MERZ法則的偏離說明纖維素和液晶基元之間是氫鍵相互作用。利用掃描電子顯微鏡、電子單纖維強力儀來表征常規(guī)纖維素紡絲液及纖維素液晶紡絲液制備的纖維,結(jié)果顯示,纖維素液晶溶液紡出的絲比純纖維素溶液紡出的絲更細,機械強度提高了 34%。
[Abstract]:Cellulose, as the most abundant renewable resource on the earth, has been paid more and more attention to its development and application. The industrialized cellulose fiber has Viscose fiber and Lyocell fiber, but there are some problems in the spinning process, such as environmental pollution, high energy consumption and so on. Ionic liquid, as a new solvent, has a strong solubility to cellulose. Cellulose / ionic liquid system has the advantages of environmental protection and easy solvent recovery, but the increase of cellulose concentration will lead to a sharp increase in the viscosity of cellulose solution system. In order to prepare "high concentration and low viscosity" cellulose liquid crystal system, cellulose liquid crystal system has been proposed. In this study, a new type of cellulose side chain liquid crystal element was designed and synthesized, the conditions for the formation of side chain liquid crystal were studied, the side chain cellulose liquid crystal was prepared, and its rheology and liquid crystal properties were studied. The cellulose fiber was prepared by dry and wet spinning. The specific research contents are as follows: the solubility and interaction force of liquid crystal element in ionic liquid were studied by turbidity test and infrared spectroscopy. The results show that at room temperature, The solubility of liquid crystal elements in ionic liquids is 5.78 wt%,. There is no chemical reaction between liquid crystal elements and ionic liquids only by physical force. The phase behavior and Rheological behavior of cellulose / liquid crystal element / ionic liquid system were studied by steady and dynamic flow test, polarizing microscope, differential scanning Calorimeter and small angle X-ray diffractometer. The results show that when the concentration of cellulose is 6 wt%, the critical concentration of liquid crystal elements for the formation of cellulose liquid crystal solution is 2 鈮，

本文編號：2497903