| 摘要: | 本論文旨在研究利用雙螺桿押出機擠壓法製備聚乳酸(Polylactic acid, PLA)/生物基聚乙烯(Bio-based PE, Bio-PE)摻合物，藉由使用生物可分解塑膠以及製程低汙染的生物基塑膠進行摻合來探討此摻合材料之加工製程與性質。實驗使用乙烯-丙烯酸酯-縮水甘油甲基丙烯酸酯三元聚合物(Ethylene-methyl acrylate–glycidyl methacrylate terpolymer, EMA-GMA)相容劑對摻合物進行相容性改善，並檢測其物理性質、熱性質、機械性質及動態機械性質。本實驗使用聚乳酸(PLA)添加生物基聚乙烯(Bio-PE, LDPE)依重量百分比(100:0、95:5、90:10、85:15、80:20、0:100 wt%)製備高分子摻合物。為了相容性的改善，添加不同含量(1phr、3phr、5phr)之EMA-GMA於各測試需求。
探討不同重量百分比的Bio-PE和不同添加百分比之EMA-GMA對摻合物的形態學(FT-IR、SEM、Raman、XRD)、物理性質（密度）、機械性質（硬度、耐磨耗指數、抗折強度、抗張強度及耐衝擊強度）、熱性質(DSC、TGA、TMA、MI、HDT)、動態機械性質(DMA)之性能和影響的差異程度。
實驗結果得知，經由FT-IR發現紅外線無法觀察PLA與Bio-PE在官能基上的變化，而X光照射的XRD及雷射照射之Raman測試可發現摻合物隨著Bio-PE含量的增加，其特徵峰皆會更加明顯，以此證明Bio-PE的存在；結構與形態學在SEM圖得知隨著Bio-PE含量的增加表面結構從原來的片狀平面變為Bio-PE覆蓋的表面，而添加相容劑EMA-GMA則會使平面變回片狀平面；物理性質的測試，PLA在添加Bio-PE時密度會因為Bio-PE添加而逐漸減少，而添加EMA-GMA則會先提升而後下降；在機械性質測試結果，發現將Bio-PE含量增加，其抗張與抗折強度與模數皆呈現下降趨勢，耐磨耗方面整體可減少約一半之磨耗，而加入EMA-GMA時則會逐漸變回原本的磨耗量。耐衝擊的測試中，隨著Bio-PE含量增加，其強度會逐漸下降，但加入3phr EMA-GMA可以提升強度；在熱性質方面，耐裂解性提高效果更加顯著。
以上結果顯示聚乳酸/生物基聚乙烯的耐熱性質、延伸率、耐磨耗都有獲得改善。而摻合物添加EMA-GMA有助於改善材料的衝擊強度與延伸率。
The purpose of this thesis is to study the preparation of Polylactic acid (PLA)/Bio-Based low density polyethylene blend (Bio based-PE，Bio-PE) by twin-screw extruder extrusion method . To explore the processing and properties of the low-pollusion blend, it was blended by biodegradable plastic and bio-based plastic.The blend was also modified with ethylene-methyl acrylate–glycidyl methacrylate terpolymer (EMA-GMA) to test its properties of physical, thermal, mechanical, and dynamic mechanical. This experiment used polylactic acid (PLA) blend in with Bio-Based low density polyethylene blend (Bio based-PE，Bio-PE，LDPE) to produce polymer blends by weight percentage (5wt%, 10wt%, 15wt%, 20wt%, 100wt%) of Bio-PE. To improve low compatibility, different rates (1phr, 3phr, 5phr) of ethylene-methyl acrylate–glycidyl methacrylate terpolymer (EMA-GMA) were added for each experiment needed.
To find out every difference between polymerblends，the results of Morphology (FT-IR , SEM , Raman , XRD) , Physical properties (Density) , Mechanical properties (Hardness, wear resistance index, strength of flexural, tensile and impact) , Thermal properties (DSC, TGA, TMA, MI and HDT), dynamic mechanical properties (DMA) are the way to analyze all .
The experimental results show that there is no bond generated in the polyblends by FTIR. XRD and Raman experiment discover characteristic peak of Bio-PE, which can prove the existence of Bio-PE. Structure and Morphology in the SEM image, which distribution is changed from smooth to drop surface with the increase of Bio-PE content and the surface will be transformed back to scatter surface with the content of EMA-GMA. The density of polyblend decreased with the higher percentage of Bio-PE and EMA-GMA. In the mechanical properties test results, tensile strength and modulus showed a downward trend when the increase in percentage of Bio-PE. Hardness decreased with the increase of Bio-PE content. The wear resistance decreased when adding Bio-PE but increased in constant of EMA-GMA. In the impact resistance test, the Bio-PE content increases, the strength decrease, and 3phr content of EMA-GMA increase the strength. In the thermal properties, more percentage of Bio-PE content, more degradation temperature increase.
The above results show that the polylactic acid Bio-Based low density polyethylene blend has improved heat resistance properties, elongation, and abrasion resistance. The addition of EMA-GMA to the blend helps to improve the elongation and impact strength of the material. |
