實驗統計法改良丙烯酸接枝中去乙醯度幾丁聚醣
之製備及應用於吸附巴拉刈

本研究是以丙烯酸(AA)改質去乙醯度45%幾丁聚醣(dAc 45% CTS)，再進行於吸附巴拉刈。以過氧化氫與氫氧化氨做為氧化還原起始劑，進行接枝共聚合反應，使得丙烯酸的羧酸基鍵結在幾丁聚醣的主鏈上。實驗的變數為過氧化氫濃度、溫度與氫氧化氨濃度。經傳統的實驗方法，獲得的最高接枝比配方為H2O2(aq)為0.78M、80℃與NH4OH(aq)為6.67×10-2M，可製得44.22%接枝百分比之CTS-g-PAA 共聚合物。再利用CCD(Center composite design) 實驗統計法，另可求得最佳配方為0.1M NH4OH(aq)、0.64M H2O2(aq)與86.5℃，依此配方計算，可製成53.6%接枝百分比之CTS-g-PAA共聚合物。實驗結果之接枝百分比為53.5?b0.3%，與理論計算一致。取用最佳配方製得之CTS-g-PAA，以FT-IR光譜分析，確定在幾丁聚醣的結構上含有丙烯酸的羧酸基。CTS-g-PAA再經水解形成鈉鹽的形式後，進行吸附巴拉刈。吸附反應初期速率極高，在20分鐘左右即可達到平衡。吸附等溫線的結果顯示Langmuir模式比Freundlich模式更能描述吸附行為。計算單層飽和吸附量qm為396.8 mg/g-吸附劑，此ㄧ結果為未改質CTS之36倍，且較傳統的活性碳、Fuller’s earth等巴拉刈吸附劑至少高出4倍。本文研製之新型巴拉刈吸附劑極有潛力未來應用於巴拉刈中毒病患之急救。

關鍵字

幾丁聚醣；丙烯酸；接枝共聚合；巴拉刈

並列摘要

Middle deacetylation Chitosan grafted poly(Acrylic acid) (CTS-g-PAA) was synthesized and characterized to obtain a new adsorbent of paraquat. The CTS-g-PAA copolymers were prepared at various concentrations of ammonium ([NH4OH]), hydrogen peroxide ([H2O2]) and temperature to find the copolymerization recipe of highest grafting percentage by using of traditional technique. The obtained recipes and grafting percentage of copolymer are 0.78M [H2O2]、80℃、6.67×10-2M [NH4OH] and 44.22%,respectively. However, the CCD (Center composite design) was also applied to find the optimum recipes in the system. The optimum recipes are 0.64M [H2O2]、86.5℃、0.1M [NH4OH]. The calculated grafting percentage of copolymer from CCD increases to 52.6%, which is consistent with the experimental results. The grafting copolymerization was confirmed by FT-IR spectra. A representative CTS-g-PAA copolymer was hydrolyzed to a salt type and applied to the adsorption of paraquat. The adsorption time to reach equilibrium was about 20 minutes. The adsorption equilibrium data correlate closely with the Langmuir than the Freundlich isotherms. The maximum adsorption capacity, qm, is 396.8 mg/g-adsorbent. This value exceeds those for Fuller’s earth and activated carbon, which are the most common binding agents currently used for paraquat. The results suggest that CTS-g-PMAA has potential use as a paraquat adsorbent.

並列關鍵字

Chitosan ； Acrylic acid ； Graft copolymerization ； Paraquat

參考文獻

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實驗統計法改良丙烯酸接枝中去乙醯度幾丁聚醣之製備及應用於吸附巴拉刈

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