- 學位論文
不同酸性改質奈米碳管對環氧樹脂之應用性研究
The Study on the Properties of CNT/epoxy Composites For Different Acidc Modification of Multi wall Carbon Nanotube
摘要
本研究針對奈米碳管，採用化學氧化法，以不同濃度、體積之硝酸、鹽酸、硫酸、混合酸作為氧化劑，對多壁奈米碳管進行表面改質，得到改質奈米碳管，並以SEM、XRD、拉曼、FT-IR分析改質前後奈米碳管之性質變化。再將改質後之奈米碳管分散於環氧樹脂當中，製成CNT/epoxy複合材料試片後進行TGA、UV-vis、PL、拉伸測試、電阻量測，比較奈米碳管改質前後添加到環氧樹脂之補強複合材料的性質變化。 實驗結果顯示，以各種酸處理會使多壁奈米碳管比未改質之碳管表面具有較多極性官能基，如羥基(-OH)和羧基(-COOH)...等，其中以FT-IR分析混合酸使奈米碳管接上官能基的效果最好，且6M酸改質分散效果較3M好，因此以UV-vis及PL分析顯示在環氧樹脂當中的分散性也最佳。鹽酸改質對碳管的分散性提升最少但添加在高分子中具有較佳的抗拉強度。硫酸改質之複合材料導電性、機械性、熱穩定性皆為最差因此判斷硫酸對碳管結構破壞性最大。硝酸改質對分散性提升效果僅次於混酸，但有最佳熱穩定性。提升分散性的同時，奈米碳管的強度也在下降，需在分散性提升與碳管結構破壞取得一個平衡點作為改質的最佳參數。
並列摘要
In this study, we focus on the carbon nanotubes which was modified by chemical oxidation with different concentrations and volume of nitric acid , hydrochloric acid, sulfuric acid , mixed acid as an oxidizing agent separately , after the modified, carbon nanotubes were studied by using SEM, XRD, Raman , FT-IR analysis compared with unmodified. Then we took the modified carbon nanotubes dispersed into the epoxy, made CNT / epoxy composite and researched by the using TGA, UV-vis, PL, tensile testing, resistance measurements , comparied the Properties of the CNT/epoxy Composites with different chemical treatment. It is found that the acid treatment causes multi-walled carbon nanotubes with induced the amount of more polar functional groups than the unmodified carbon nanotubes surface such as hydroxyl group (-OH) and carboxyl group (-COOH) ... etc. FT-IR analysis showed that carbon nanotubes modified by mixed acid enable to connected functional group with the best effect. Therefore it had the best Dispersion in the epoxy than al l were displayed in UV-vis and PL analysis . The Carbon nanotubes modified by Hydrochloric acid to enhance the dispersion in the epoxy,and had the best tensile strength than all. The Carbon nanotubes modified by sulfuric acid added into epoxy composite had the worst conductivity, mechanical properties and thermal stability because of the most devastating structure from sulfuric acid treatment, and nanotube modified by Nitrate to enhance the the dispersion in epoxy were not as well as the effect by mixed acid treatment, but composite had the best thermal stability. The carbon nanotube modified by acidc chemical treatment would enhance to the dispersion in epoxy , while the strength of carbon nanotubes also decreasing .We need to improve the dispersion of carbon nanotubes and structural devastating to strike a balance as a modification of the optimal parameters .