阻燃聚乳酸複合材料之研究與探討

A study of flame retarded poly(lactic acid) composites

王妤盈(Yu-Ying Wang)

指導教授 ： 石燕鳳

朝陽科技大學/理工學院/應用化學系/碩士(2012年)

摘要

本研究主要是以聚乳酸(Poly(lactic acid)，PLA)生物可分解塑膠作為基材，並添加了10%聚琥珀酸丁酯(Poly(butylene succinate),PBS)，提升基材韌性，並以回收竹筷纖維作為補強材。竹筷纖維經初步處理先乾燥、粉碎、過篩，經由鹼處理、偶合劑處理之表面改質以提升補強材與基材間相容性及提升機械性質，為了有效提升聚乳酸的結晶速率添加5phr奈米黏土成核劑促使熱穩定性較佳，並結合聚磷酸胺及膨脹石墨等兩項阻燃材料，以雙螺桿混煉機混摻製備出具阻燃性之生物可分解性複合材料。研究結果顯示，阻燃材料聚磷酸胺與膨脹石墨最佳比例為1:5；可達UL-94耐燃試驗V-0等級；SEM測試結果顯示纖維表面改質後可有效的提升複合材料的界面黏著性，而抗張強度及耐衝擊測試分別可提升14.7%、5.4%，另由TGA及DSC觀察得知熱穩定性有明顯改善；其熱變形溫度最佳可提升102%。而本實驗所再利用竹筷纖維不僅可提升材料機械性質，並可有效的降低成本及合乎綠色環保之需求。

關鍵字

回收竹筷纖維 ； 聚乳酸 ； 膨脹石墨 ； 聚磷酸胺 ； 阻燃性 ； 複合材料

並列摘要

In this study, the polylactic acid (poly (lactic acid), PLA) biodegradable plastic was as a substrate, and 10% Poly (butylene succinate,), PBS),was added to enhance the toughness of the substrale, as well as recycled bamboo chopsticks fiber was added as reinforcement material. The preliminary processing of chopsticks fiber was : drying, crushing, alkali treatment and surface modification of the coupling agent, so as to enhance the compatibility between reinforcement and PLA, and improve the mechanical properties of PLA. In order to effectively enhance the crystallization rate of PLA, 5 phr nano-clay was added as a nucleating agent to promote the thermal stability of PLA. Moreover, polyphosphoric acid amine and expandable graphite were added as flame-retardants. Then the biodegradable composites were prepared by the twin-screw mixer. The results show that the optimum ratio of polyphosphate amine and expandable graphite is 1:5, the UL-94 flame test can reach V-0 grade. SEM analysis revealed that the interfacial dhesion of composite was effectively enhanced after the surface modification of fiber. The increments of tensile and impact strength were 14.5%, 5.5%. TGA and DSC analyses show that thermal stability have been improved significantly; the increment of heat distortion temperature can reach 102%. In this study, the re-use of chopsticks fiber can not only improve the mechanical properties of materials, but effectively reduce the costs of materials and meet the demand for green policy.

並列關鍵字

flame retardant ； composites. ； ammonium polyphosphate ； recycled disposable chopsticks fiber ； expandable graphite ； polylactic acid

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