纖維素奈米纖維(Cellulose Nanofiber, CNF)為具有高強度比、生物可降解的奈米材料，十分具有應用的潛能。本研究以農業廢棄物稻草當作原料，並且經由鹼萃及漂白將雜質去除，萃取出纖維素，再利用2,2,6,6-四甲基哌啶-1-氧化物(2,2,6,6-Tetramethylpiperidine-1-oxyl , TEMPO)氧化法將纖維素表面改質，最後利用超音波震盪製備CNF。
本研究的第二階段為製備CNF與PMMA的複合材料，研究其機械性質以及磨潤性質。先以OM觀察CNF在聚甲基丙烯甲酯(PolyMethyl MethAcrylate, PMMA)中的分散效果，發現在較高填料添加量的情況下會發生較嚴重的聚集，在傅立葉轉換紅外線光譜儀(Fourier-transform infrared spectroscopy, FTIR)的測試結果說明PMMA與CNF中並無產生新的鍵結，熱示差掃描量熱儀(Differential scanning calorimetry, DSC)所計算的玻璃轉換溫度無明顯的改變再一次證明PMMA與CNF為相容性不高的材料，在相容性不高及分散較良好的情況下可以提高機械性質。在磨潤性質方面由於加入CNF提高表面硬度，以及CNF的潤滑效果，使得複合材料的磨潤性質有明顯的提升。

Cellulose Nanofiber (CNF) is a biodegradable nanomaterial with high specific strength, which has great potential for application. In this study, agricultural waste rice straw was used as the raw material, and the impurities were removed by alkaline process(AP) and bleaching process(BP). Then the cellulose was surface modified by TEMPO oxidation, and prepared CNF by ultrasonic process.
Prepare CNF and PMMA composite materials, study its mechanical properties and wear properties. Observe the distribution of CNF in PMMA by OM. It is found that more filler addition the more serious aggregation will occur. So that adding more than 0.1 wt.% CNF, tensile strength and breaking strain are significantly decrease. In terms of wear properties, the addition of CNF can improve hardness. And the lubricating effect of CNF, which significantly improves the wear properties of composite materials.

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