利用木质素前驱物协同果胶在漆酶体系作用下处理麦草纤维,以湿法工艺制造高强度中密度纤维板.实验结果表明:经处理后,纤维板的24 h吸水厚度膨胀率(TS),纤维板的内结合强度(IB),静曲强度(MOR),弹性模量(MOE)分别达到16.7％,0 6MPa,25.1MPa,2 500 MPa.各项物理性能指标均达到或超过国家中密度纤维板(GB/T 11718 -2009)标准.通过SEM和CP/MAS 13C NMR分析可知,在木质素和聚糖(果胶等)之间发生了交联反应,形成了类似胞间层的沉积物,通过苯甲醚、酯键等木质素-聚糖复合体形式的交联以及木质素之间的β-芳基醚键等共价键的连接,从而使纤维之间形成牢固的化学键交联.同时研究还发现,果胶与松柏醇葡萄糖苷很容易生成果胶-DHP复合体,从而进一步提高了纤维板的物理性能,同时降低TS.%In the present research, coniferin-[α-13C]is rio-polymerized with fibers of Bio-CMP of wheat straw and pectin catalyzed by laccase. A wet method was used for the formation of high-strength fiberboards. The results indicated that the thickness expansion rate of water absorbing (TS) , the internal bond ( IB) , the modulus of rupture ( MOR) , and the modulus of elasticity (MOE) reached 16.7 %, 0.6 Mpa, 25.1 Mpa and2 500 Mpa. Respectively. As a result, all mechanical properties of the medium-density fiberboard ( MDF) can meet or exceed the standards of GB/T 11718 -2009. According to CP/MAS 13C NMR, lignin-carbohydrate complexes( LCC) were formed between lignin and polysaccharide. Pectin and xylan in fibers were crosslinked with high through benzyl ether linkages and ester bonds, and β-aryl ether linkages were formed between lignin. Furthermore, pectin and coniferin were easy to form pectin-DHP in the presence of laccase. These complexes and linkages result in a further improvement of mechanical properties of MDF and reduction of TS.
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