漆酶介体体系活化木质素制备环保型纤维板及其性能表征

Performances of Environment-friendly Fiberboard Prepared by Laccase-mediator System Modified Ammonium Lignosulfonate

以木纤维为基体,漆酶-HBT介体体系活化后的木质素磺酸铵(LMS/AL)为黏合剂制备环保型纤维板(LMS/ALF),利用傅里叶变换红外光谱(FT-IR)、X射线衍射仪(XRD)和环境扫描电子显微镜(ESEM)分别分析材料的化学组分、结晶度和微观形貌,并通过正交试验对漆酶用量、介体用量、活化时间和温度4个工艺参数进行优化。结果表明,最优的工艺参数为漆酶添加量20 U/g,介体添加量0.3%,活化时间60 min,活化温度50℃。在此最优工艺条件下制备的环保型纤维板,与采用漆酶活化木质素磺酸铵为黏合剂制备的中密度纤维板(Lac/ALF)相比,内结合强度提高了16.67%,静曲强度提高了20.35%,弹性模量提高了7.96%,吸水厚度膨胀率降低了12.95%,其力学性能均已达到GB/T 11718—2009中干燥状态下使用的普通型中密度纤维板的性能要求。

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 were20 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.