微纤化纤维素及其制备技术的研究进展

摘要

微纤化纤维素（MFC）是一种主要由植物纤维制备而得的可再生高分子材料，兼具天然纤维和纳米材料的特点。近年来，有关MFC制备、改性及应用方面的研究越来越多，然而制备成本高、干燥以及再分散等仍然是MFC规模化生产所不可回避的问题。为了更全面地加深对MFC及其制备技术发展现状的认识，本文首先探讨了MFC物化特性及其命名，然后介绍了MFC机械制备方法，包括高压均质处理、微射流处理、超细研磨处理、冷冻破碎处理和高强超声处理等，并对MFC机械制备存在的问题进行了分析。本文还介绍了MFC制备过程中的预处理方法，包括纤维素酶预处理、酸-碱抽提预处理、羧甲基化预处理、TEMPO氧化预处理、高碘酸盐氧化预处理等。最后对MFC在规模化生产及干燥过程中存在的问题进行了总结。%Microfibrillated Cellulose(MFC)is a renewable macromolecular material derived from lignocellulosic fiber,which possesses the characteristic of natural cellulose and nanomaterials. Recently,many studies have been carried out in the preparation,modification,and application of MFC. However,its application is hampered by the high cost,dry methods and re-dispersability,especially in large scale production of MFC. To better understand the properties and progress of microfibrillated cellulose preparation,the characteristic and definition of MFC were firstly investigated,and the different mechanical preparation methods of MFC were discussed,including high pressure homogenization treatment,microfluidization treatment,ultrafine grinding treatment,cryocrushing treatment and high intensity ultrasonication treatment. Subsequently,the problems of mechanical preparation of MFC were analyzed. The pretreatment methods for MFC preparation were also presented,including cellulase pretreatment,alkaline-acid pretreatment,carboxymethylation pretreatment,TEMPO oxidation pretreatment,and periodate oxidation pretreatment. Finally,the problems existing in the preparation and dry process of MFC in large scale were summarized.