Laccase-Mediator Catalyzed Modification of Wood Fibers: Studies on the Reaction Mechanism and Making of Medium-Density Fiberboard
Laccase-Mediator Catalyzed Modification of Wood Fibers: Studies on the Reaction Mechanism and Making of Medium-Density Fiberboard
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DOI：
10.13073/fpj-d-12-00075
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发表时间：
2013-01-01
影响因子：
0.9
通讯作者：
Kharazipour, Alireza
中科院分区：
文献类型：
--
作者：
Euring, Markus;Trojanowski, Jerzy;Kharazipour, Alireza
由于石化树脂工艺的价格不断上涨以及工业生产的中密度纤维板（MDF）可能释放有害的甲醛，酶粘合剂系统被讨论为用于胶合木质纤维素如木纤维的环境友好的替代方案。在这项工作中，漆酶介体系统（LMS）被用来激活木质素的木材纤维表面。测试了两种不同的介质，香草酸（货车）和4-羟基苯甲酸（IBA），其中HBA表现最好。采用碳13核磁共振（C-13-NMR）和电子自旋共振（ESR）技术对热磨机械浆（TMP）纤维的活化过程进行了定性和定量分析。将分析输出转移到使用干法工艺生产的样品中。13 C-NMR揭示了使用LMS与HBA比LMS与货车的木材纤维中更多的结构变化。ESR光谱表明，更高的量的苯氧基自由基处理后的LMS含有HBA作为介体。这些数据与质量相关性良好。通过在LMS中使用HBA，获得了最佳的机械工艺性能，从而可以满足欧洲规范。但货车也表现良好，这表明在未来通过使用LMS生产生态友好型作物的潜力很大。
Owing to the constant increase of prices of the process for petrochemical resin and the possibility of harmful formaldehyde emissions from industrial produced medium-density fiberboards (MDF), enzymatic binder systems are discussed as an environmentally friendly alternative for gluing lignocelluloses such as wood fibers. In this work laccase-mediator systems (LMSs) were used to activate the lignin on wood fiber surfaces. Two different mediators were tested, vanillic acid (VAN) and 4-hydroxybenzoic acid (}IBA), of which HBA performed best. Carbon-13 nuclear magnetic resonances (C-13-NMR) and electron spin resonances (ESR) of LMS-treated thermomechanical pulp (TMP) fibers were determined for qualitative and quantitative analysis of lignin activation. Analysis outputs were transferred to produce MDF using a dry process. 13C-NMR revealed more structural changes in the wood fibers using LMS with HBA than LMS with VAN. ESR spectroscopy indicated a higher amount of phenoxy radicals after treatment with LMS containing HBA as a mediator. The data correlated well with the quality of MDF. The best mechanical technological properties were achieved by using HBA within the LMS, so that the European Norms could be fulfilled. But VAN also performed well, which showed a high potential to produce ecofriendly MDF by using LMSs in the future.