奈米纖維/聚乳酸綠色複合材料之研究

A Study of Nanofiber / Polylactic Acid Green Composites

張翼(Yi Jhang)

指導教授 ： 石燕鳳

朝陽科技大學/理工學院/應用化學系/碩士(2014年)

摘要

本研究將奈米木質纖維經由冷凍乾燥技術，使奈米纖維有效的去除水分，過程中利用控制奈米纖維懸浮液的濃度來降低奈米纖維乾燥後之團聚現象，製備一系列之奈米纖維/聚乳酸複合材料。透過懸浮液處理，可降低奈米纖維之尺寸大小及增加比表面積，藉以提升奈米纖維與聚乳酸間的界面相容性及分散性，最後以熔融混煉的方式製備出複合材料。結果顯示，經過懸浮液處理後的奈米纖維可以提升與聚乳酸間的界面相容性，有效改善複合材料之機械性質與熱性質。由熱變形溫度分析，最高可提升49.05%；機械性質測試在奈米纖維添加0.5、1wt%時有較佳的性質，抗張強度最高提升29.74%，耐衝擊強度最高提升57.17%。從SEM分析可以觀察到奈米纖維與聚乳酸間緊密性良好，沒有明顯的孔洞產生，在斷裂面中的奈米纖維呈現截斷沒有被拔出的現象；從透光性測試中可以得知，當奈米纖維經過懸浮液處理，與聚乳酸製成薄膜能有效提升分散性進而提升薄膜的透光性。由以上結果顯示，添加了懸浮液處理的奈米纖維能提升聚乳酸之熱性質與機械性質，並且提高了複合材料之透明性。

關鍵字

複合材料 ； 奈米纖維 ； 聚乳酸

並列摘要

In this study, the moisture of cellulose nanofibers from wood were effectively removed via freeze-dried technology. During this process, the agglomeration of nanofibers was reduced by controlling the concentration of nanofiber suspensions. Moreover, the dimension of the nanofibers will be reduced and the specific surface area will also be increased. Subsequently, the interfacial compatibility and dispersion between nanofibers and polymer matrix can be improved. Finally, a series of nanofibers/polylactic acid (PLA) composites are prepared by melt-blending. The results reveal that the interfacial compatibility between the PLA and nanofibers was improved after suspension treatment, so that the mechanical and thermal properties of the composites are elevated effectively. The heat deflection temperature test shows an increase of approximately 49.05% for PLA. In addition, the tensile and impact strengths increase around 29.74% and 57.47%, respectively when the composite material is reinforced with 0.5 and 1wt% content of suspension-treatment nanofibers. The better compatibility between nanofibers and PLA can be observed from SEM analysis that no hole is found and the nanofibers exhibit the phenomenon of truncating instead of pulling-out on the fracture surface. Moreover, the test of diaphaneity reveals that the transparency of the film can be effectively enhanced by the suspension treatment. The results show that the addition of the suspension-treatment nanofibers into PLA not only increases the mechanical and thermal properties of PLA, but also enhances the diaphaneity of the composite material

並列關鍵字

composite material ； nanofibers ； polylactic acid

參考文獻

15. 羅佑旭，奈米材料化學，東華大學，花蓮，(2003)

1. Bogoeva G., “Natural Fiber Eco-composites”, Polymer Composites, 28(10), 98-107(2007)

2. Mohini S., Suhara P., “Bioprocess preparation of wheat straw fibers and their characterization”, Industrial Crops and Products, 23 , 1-8(2006)

7. 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，朝陽科技大學應用化學系碩士論文，台中，(2013)

13. Habibi Y., Lucia L. A., Rojas O. J., “Chem.Cellulose Nanocrystals: Chemistry, Self-Assembly, and Applications” , Chemical Reviews, 110(6), 3479− 3500, (2010)