化學改質植物纖維/聚乳酸綠色複合材料之研究

A Study of Chemically Modified Plant Fiber/ Polylactic Acid (PLA) Green Composites

許志偉(Chih-Wei Hsu)

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

本研究目的在改善農業廢棄物鳳梨葉纖維(Pineapple leaf fiber)與聚乳酸(Poly lactic acid, PLA)的複合材料之界面相容性，藉以提升複合材料的機械性質與耐熱性。運用具反應選擇性構築單元之化合物(4-isocyanato-4'-(3,3-dimethyl-2,4-dioxoazetidino)diphenylmethane, IDD)進行聚乳酸改質，製備改質聚乳酸，再與改質鳳梨葉纖維進行熔融混摻，製備一系列的高性能的改質鳳梨葉纖維/改質聚乳酸複合材料。實驗結果顯示，得知當植物纖維添加15%時其熱變形溫度(HDT)得到較佳的性質改善，最高可提升70.18%；當植物纖維添加5%，可使機械性質測試得到較佳的改善，抗張強度最高可以提升14.07%，耐衝擊強度最高可以提升10.71%。從SEM分析可以觀察到纖維與改質聚乳酸間無纖維抽出或孔洞等現象。由以上結果顯示，經改質後聚乳酸與鳳梨葉纖維之間的界面相容性可以有效的提升，並有效改善複合材料之機械性質與熱性質。不僅能提升聚乳酸複合材料之熱性質與機械性質，並提供一種新的可以有效提升複合材料界面相容性的路徑。

關鍵字

鳳梨葉纖維 ； 聚乳酸 ； IDD ； 複合材料

並列摘要

The objective of this study is to improve the interfacial compatibility of pineapple leaf fiber/polylactic acid (PLA) composites, and to enhance the mechanical properties and heat resistance of the composites. The 4-isocyanato-4'-(3,3-dimethyl-2,4-dioxoazetidino) diphenylmethane (IDD) which has reactive selectivity is used to modify the PLA. Then, the IDD modified PLA and the pineapple leaf fibers are melt-blended to prepare a series of high-performance pineapple leaf fiber/modified PLA composites. The results showed that the compatibility of the composite was effectively improved, and the mechanical and thermal properties of composite were elevated after the IDD modification of PLA. The heat deflection temperature (HDT) test showed an increase of approximately 70.18% for PLA. In addition, the tensile and impact strengths of pristine PLA were increased about 14.07% and 10.71%, respectively, when the composite material reinforced with 5% of fibers. SEM analysis showed that the compatibility between the SAF and IP matrix is improved as evidenced by the absence of pull-out fiber and voids on the fracture surface. These results show that the pineapple leaf fibers/IDD modified PLA composites not only enhance the thermal and mechanical properties of PLA, and provide a new method to improve the interfacial compatibility.

並列關鍵字

pineapple leaf fiber ； polylactic acid ； IDD ； composite

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