張永明 郭明輝 李傳明
(生物質材料科學與技術教育部重點實驗室(東北林業大學),哈爾濱,150040) (吉林省天橋嶺林業局)
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漆酶介體體系活化木質素制備環保型纖維板及其性能表征1)
張永明郭明輝李傳明
(生物質材料科學與技術教育部重點實驗室(東北林業大學),哈爾濱,150040)(吉林省天橋嶺林業局)
以木纖維為基體,漆酶-HBT介體體系活化后的木質素磺酸銨(LMS/AL)為黏合劑制備環保型纖維板(LMS/ALF),利用傅里葉變換紅外光譜(FT-IR)、X射線衍射儀(XRD)和環境掃描電子顯微鏡(ESEM)分別分析材料的化學組分、結晶度和微觀形貌,并通過正交試驗對漆酶用量、介體用量、活化時間和溫度4個工藝參數進行優化。結果表明,最優的工藝參數為漆酶添加量20 U/g,介體添加量0.3%,活化時間60 min,活化溫度50 ℃。在此最優工藝條件下制備的環保型纖維板,與采用漆酶活化木質素磺酸銨為黏合劑制備的中密度纖維板(Lac/ALF)相比,內結合強度提高了16.67%,靜曲強度提高了20.35%,彈性模量提高了7.96%,吸水厚度膨脹率降低了12.95%,其力學性能均已達到GB/T 11718—2009中干燥狀態下使用的普通型中密度纖維板的性能要求。
漆酶介體體系;木質素磺酸銨;環保型纖維板;工藝參數;性能表征
We developed a highly effective method for preparing environment-friendly medium density fiberboard (MDF) with high performance, using ammonium lignosulfonate modified by laccase-HBT mediator system (LMS/AL) and natural wood fiber as wood adhesives and raw materials. We analyzed the LMS/AL, MDF and the fractures in the bonded joints by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and environmental scanning electron microscopy (ESEM) and the optimal modifying parameters were researched by orthogonal test. The optimal modifying parameters were 20 U/g of laccase dosage, 0.3% of mediator dosage, 60 min of activation time and 50 ℃ of activation temperature, and the performance of MDF using LMS/AL as adhesives improved significantly than that of MDF using ammonium lignosulfonate modified by laccase (Lac/ALF) only as adhesives.
近年來,隨著礦物質資源的減少,以石油等不可再生資源為原料的膠黏劑的價格開始不斷上漲,人們已經開始關注游離甲醛對人體的危害,開發利用可再生的生物質資源作為膠黏劑制備綠色環保型木質基復合材料已成為研究熱點[1-2]。工業木質素是造紙制漿廢液中主要的副產品,根據工藝的不同可將其分為木質素磺酸鹽、水解木質素、堿木質素和新型制漿法木質素4大類[3]。……