基板處理與塗佈方式對纖維素薄膜表面性質之影響

Influence of Substrate Treatments and Coating Methods on Surface Characteristics of Cellulose Films

蔡承諭(Chen-Yu Tsai)

指導教授 ： 柯淳涵

國立臺灣大學/生物資源暨農學院/森林環境暨資源學研究所/碩士(2019年)

https://doi.org/10.6342/NTU201901557

摘要

纖維素原料是一種可再生、生物可降解的綠色永續材料。本研究使用微晶纖維素和漂白漿為原料，經過磷酸前處理過後的纖維素原料以N-甲基嗎晽-N氧化物水溶液作為溶劑製成纖維素溶液，然後將纖維素溶液以旋轉塗佈法和夾層法製備出纖維素薄膜。在塗佈的過程中，使用未處理的矽晶片、用粒徑1微米的鑽石砂紙刮磨過的矽晶片以及用鑽石砂紙刮磨後再以3-氨基丙基三乙氧基矽烷進行矽烷化處理的矽晶片作為基板。研究結果顯示，已經成功地發展出製備具有優選取向的纖維素薄膜的方法。原物料、塗佈方式、基板處理會影響薄膜中奈米結晶纖維素的排列。其中以Avicel為原料，以夾層法塗佈並搭配用鑽石砂紙刮磨過的矽晶片為基板所製備出的纖維素薄膜具有最佳的方向性。其厚度為6.92 ± 0.37 μm，粗糙度為30.01 nm，具有明顯的層狀結構。在低掠角繞射的結果中，在2θ為10.50°處出現具有方向性的訊號。偏光顯微鏡圖中，5CB (4-cyano-4'-pentylbiphenyl) 液晶分子整齊地朝著刮磨方向排列。

關鍵字

纖維素薄膜 ； 優選取向 ； 夾層法 ； 刮磨處理 ； 矽烷化 ； 低掠角繞射

並列摘要

Cellulosic feedstocks are renewable, biodegradable and eco-friendly materials. In this study, cellulosic feedstocks including Avicel and bleached eucalyptus kraft pulps which are pretreated by phosphoric acid are dissolved with N-methylmorpholine-N-oxide (NMMO) to prepare cellulose solution. Cellulose solution is coated as a cellulose film by spin coating and sandwich method. During the coating process, untreated silica wafer, silica wafer which is scratched by diamond sandpaper with 1μm particle size and silica wafer which is scratched by diamond sandpaper plus silanized with (3-aminopropyl)triethoxysilane (APTES) are used as substrates. The experimental results indicate that preparation methods of cellulose film with preferred orientation is successfully developed. Cellulosic feedstocks, coating methods and substrate treatment have influence on arrangement of cellulose nanocrystals in cellulose film. Well aligned cellulose film can be obtained from Avicel by sandwich method with scratching substrate treatment. Thickness of this cellulose film is 6.92 ± 0.37 μm, roughness is 30.01 nm and there is pseudolayered helical structure. The result of grazing incidence X-ray diffraction (GIXD) shows that the directional signal is at 2θ = 10.50°. In polarizing optical microscope (POM) image, liquid crystals, 4-cyano-4'-pentylbiphenyl molecules (5CBs) are well aligned on the cellulose film surface.

並列關鍵字

cellulose film ； preferred orientation ； sandwich method ； scratching treatment ； silanization ； grazing incidence X-ray diffraction

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