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題 名 | 固態光譜法解析乙醯化雲杉之反應特性=Characterization of Acetylated Sitka Spruce (Picea Sitchensis Carr.) by Solid State Spectroscopy |
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作 者 | 張上鎮; 張惠婷; 王升陽; | 書刊名 | 中華林學季刊 |
卷 期 | 31:4=123 1998.12[民87.12] |
頁 次 | 頁405-413 |
分類號 | 436.18 |
關鍵詞 | 木材; 乙醯化; 光電子能譜分析; 散反射紅外線光譜; 固態核磁共振光譜; 化學結構; 結晶度; Solid state CP/MAS丨C-NMR; Wood; Acetylation; ESCA; DRIFT; Chemical structure; Degree of crystallinity; |
語 文 | 中文(Chinese) |
中文摘要 | 為了探討木材乙醯化之反應特性,本試驗以光電子能譜(ESCA)、散反射紅外線光譜 (DRIFT)與固態核磁共振光譜(CP/MAS □C-NMR)等直接分析固態之乙醯化木材。以ESCA分析乙 醯化雲杉(Picea sitchensis Carr.)組成分中碳、氧分子之鍵結型式,得知C4(O-C=O)與O1(C=O) 含量會隨著重量增加率(WPG)之上升而逐漸增加,即乙醯基之比例隨之提高。又由DRIFT與固 態CP/MAS □C-NMR分析結果亦顯示,雲杉組成分的羥基含量減少,而乙醯基含量增多,由此 證實雲杉以醋酸酐處理,組成分中羥基的氫原子為乙醯基所取代而產生乙醯化反應,且反應位 置主要發生在全纖維素非結晶區C-6之羥基與C-2之羥基,此外,木質素之羥基亦產生反應。 另外,由固態CP/MAS □C-NMR與X-ray繞射分析結果得知,乙醯化雲杉的結晶度與未處理材 相近,顯示重量增加率為18.61%以下時,乙醯化處理並不會對纖維素產生明顯的降解作用。 |
英文摘要 | Solid state spectroscopic methods, including electron spectroscopy for chemical analysis (ESCA), diffuse reflectance Fourier transform infrared spectroscopy (DRIFT), and solid state CP/MAS □C-nuclei magnetic resonance spectroscopy (CP/MAS □C-NMR) were used to elucidate the reaction of sitka spruce (Picea sitchensis Carr.) after acetylation. The ESCA spectrum of the acetylated sitka spruce demonstrated that the relative amounts of both C4 (O-C=O) and O1 (C=O) were increased with increasing the amount of weight percent gain (WPG), indicating the content of acetyl group was increased with the extent of acetylation of sitka spruce. The DRIFT spectrum showed that the hydroxy groups of sitka spruce were decreased and the amount of acetyl groups was increased after acetic anhydride treatment. During acetylation the hydrogen atoms of hydroxy groups were partially substituted by the acetyl groups. The analyses from the solid state CP/MAS □C-NMR of acetylated sitka spruce revealed that acetylation occurred at the amorphous region of C6 and the C2 position of the holocelluloses as well as at the hydroxy groups of lignin. Both CP/MAS □C-NMR and X-ray diffraction analyses indicated that the degree of crystallinity of cellulose remained nearly constant after acetylation with WPG less than 18.61%. |
本系統中英文摘要資訊取自各篇刊載內容。