再生纖維素薄膜之纖維方向性與其性質探討

Arrangement of Cellulose on the surface and Properties of Regenerated Cellulose Films

楊宗仁(Tsung-Jen Yang)

指導教授 ： 柯淳涵

國立臺灣大學/生物資源暨農學院/森林環境暨資源學研究所/碩士(2015年)

https://doi.org/10.6342/NTU201800036

摘要

纖維素為大自然中最豐富的綠色高分子材料，每年平均由植物細胞壁中可得約有1×1011公噸產量。因其具有生物可降解性、可再生、以及對環境衝擊小等性質。然而麻竹中含有40-50%的纖維素，其具有高生長速度及可再生性，並富有韌性與光澤，是一種具有高度潛力與成長空間的經濟樹種。本研究主要以市售的竹漿漿板，並使用對環境較為友善，且具有高回收特性的N-甲基嗎晽-N的氧化物水溶液(NMMO)作為溶劑，用來溶解市售的竹漿漿板，並製造成再生纖維素薄膜。此外也使用氫氧化鈉及過氧化氫作為竹漿漿板的前處理溶劑，用來探討經前處理後所製成的薄膜使否具有差異性。而本研究主要目的為觀測在薄膜表面的纖維束，使其朝同一方向排列並具有特定的方向性，以及使這些細小的纖維具備整齊度和均質的特性。然而只要藉由添加商用的室溫液晶(5CB)至薄膜表面，就可以簡便的在偏光顯微鏡(POM)下進行表面纖維束的觀測。除此之外，纖維排列的方向性也可藉由掃描式電子顯微鏡(SEM)進行觀測，故可藉此來證明，以POM取代複雜且耗時的SEM，用來觀測纖維束在薄膜表面上方向性的可行性。
根據結果顯示，再生纖維素薄膜表面的纖維方向性，會受到轉速及紙漿濃度的影響，隨著轉速提高及紙漿濃度降低，使其纖維排列的方向性較為明顯。此外黏度和聚合度也是影響纖維排列的重要因子，由氫氧化鈉或過氧化氫處理後的竹漿，其聚合度會明顯降低許多。如果在相同紙漿濃度的情形下，經過NMMO溶解後可以發現到殘留的粗纖維明顯減少，而對於製造而得的再生纖維素薄膜，其纖維排列的方向性也變得較明確。此外也可以發現到，因為聚合度的降低，導致所製造而得的薄膜，其較為平整且均質。因此纖維在薄膜表面上具有特定方向性以及平整且均勻度高的薄膜，將可利用在不同的範疇中。

關鍵字

N-甲基嗎晽-N-氧化物(NMMO) ； 偏光顯微鏡 ； 溶解漿 ； 再生纖維素薄膜 ； 纖維束 ； 方向性

並列摘要

This research depends on using N-methylmorpholine-N-oxide (NMMO) solution as solvent toward commercial dissolved pulps to produce regenerated cellulose films, whereas sodium hydroxide (NaOH) and hydrogen peroxide (H2O2) is used as the pretreatment of solution. The purpose is to make the fiber bundles neatly and homogeneously aligned in the same direction on the surface of films. We can observe the arrangement of fiber bundles or liquid crystals simply by adding the 4-Cyano-4'-pentylbiphenyl (5CB) in the surface under the polarizing optical microscope (POM) and verify the results by using the scanning electron microscope (SEM). In this case, it is a simple operation by POM which can replace the complex and time-consuming SEM.
The results indicate that the orientation of fiber bundles on the surface of regenerated cellulose film is obvious by increasing the rotational speed or decreasing the concentration of pulps. However, the viscosity and degree of polymerization (DP) are also important factors. The DP value will be reduced after pretreatment of the sodium hydroxide (NaOH) or hydrogen peroxide (H2O2) with different time resulting in the evident arrangement of fiber bundles. The arrangement of fiber bundles is indeed the same as the spinning tangential direction. As a result, this regenerated cellulose film can be applied in many different fields.

並列關鍵字

N-methylmorpholine-N-oxide (NMMO) ； Polarizing optical microscope (POM) ； dissolved pulps ； Regenerated cellulose film ； Fiber bundles ； Orientation

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