微纖絲化纖維素及纖維素補強聚乳酸複合材料之比較探討

A Study of Microfibrillated Cellulose and Cellulose Reinforced Polylactic Acid Composites

陳志良(Chee-Leong Chan)

指導教授 ： 石燕鳳

朝陽科技大學/理工學院/應用化學系/碩士(2015年)

摘要

本研究目的在於比較與探討鳳梨葉纖維PLF及微纖絲化纖維素MFC於不同添加量下對於聚乳酸（PLA）機械性質與熱性質的影響。其中是藉由TEMPO氧化系統進行PLF纖維的微纖絲化反應，製備出所需的MFC，此外本研究也藉由溶膠-凝膠法以TEOS為前驅物進行纖維的表面改質，得到改質後的鳳梨葉纖維SGLF及微纖絲化纖維素SGC。將不同纖維與PLA進行熔融混摻，製備出一系列的綠色複合材料。實驗結果顯示，SGC添加5 wt%時其熱變形溫度（HDT）提升最為顯著，最高可以提升30.56%；機械性質方面，SGLF添加3 wt%提升較為顯著，分別在拉伸強度提升31.58%及耐衝擊強度提升20.98%。添加纖維素至複合材料中都有效提升其儲能模數與損失模數，表示纖維素的添加可以補強聚乳酸的剛性以及韌性。從SEM分析斷裂面可觀察到表面改質後纖維與PLA相容性提升並且無拔出現象，而MFC均勻分散於PLA中。透光性測試中可以得知複合材料中以添加1 wt% MFC透光性極佳。由以上結果總結得知，鳳梨葉纖維素及微纖絲化纖維素是可以有效補強聚乳酸的機械性質與熱性質，由於鳳梨葉纖維是鳳梨收成後的廢棄物，因此作為複合材料之補強劑，不僅可以降低工業上的成本，更能降低其廢棄量，及發揮再利用的價值。

關鍵字

微纖絲化纖維素 ； 鳳梨葉纖維 ； 聚乳酸 ； 複合材料

並列摘要

The aim of this study is to compare the influence of mechanical and thermal properties of polylactic acid (PLA) reinforced with different cellulose such as pineapple leaf fiber (PLF) or microfibrillated cellulose (MFC). The MFC was obtained by the TEMPO-mediated oxidation of PLF. Moreover, surface modified pineapple leaf fiber (PLF) or microfibrillated cellulose (MFC) were prepared by modification of PLF or MFC through sol-gel reaction. Finally, a series of green composites were prepared by melt-blending. The results revealed that heat deflection temperature shows an increase of 30.56% with reinforced by 5 wt% of SGC. Besides, tensile strength was increased approximately 31.58% and impact strength was increased about 20.98% with reinforced by 3 wt% of SGLF. The storage and loss modulus of the composites can be enhanced by addition of cellulose effectively. These results showed that cellulose can reinforce the rigidity and toughness of PLA. The compatibility of fiber with PLA can be enhanced by surface modification of the fiber, which can be observed by SEM analysis. Furthermore, the MFC uniformly dispersed in PLA was also found in SEM analysis. In addition, the test of diaphaneity revealed that the composite reinforced by 1 wt% MFC has excellent transparency. These results showed that PLF and MFC can enhance mechanical and thermal properties of PLA. Pineapple leaf fibers are the waste after harvest, therefore it can reduce the costs of the composites. Moreover, the pineapple leaf fibers can be reduced and re-used as utilized as reinforcement in composites.

並列關鍵字

microfibrillated cellulose ； pineapple leaf fiber ； PLA ； composite

參考文獻

11. 嘉義農業試驗分所，http://www.caes.gov.tw

44. 黃仁宏，溶膠-凝膠法改質植物纖維/聚乳酸複合材料之製備及其特性分析，碩士論文，朝陽科技大學應用化學系，2013年。

2. Spence, Kelley Lynn, Processing and Properties of Microfibrillated Cellulose, North Carolina State University; 2011.

7. L.-T. Lim, R. Auras, M. Rubino, Processing technologies for poly(lactic acid), Progress in Polymer Science, 33, 820-52 (2008).

8. O. Faruk, A. K. Bledzki, H.-P. Fink, M. Sain, Biocomposites reinforced with natural fibers: 2000-2010, Progress in Polymer Science, 37, 1552-96 (2012).