木质素酚的结构调控及其对复合材料性能的影响

Lignocellulosic polymers play an important role in the developments of bio-based fuels and products as substitutes for those derived from the petroleum. A recent emphasis has been on the isolation and utilization of the polysaccharide (cellulose and hemicelluloses) components. However, the resulting lignin residue being poor in chemical reactivity has rather limited polymer applications. On the other hand, it is well known that wood substrates, when mixed with phenol and strong acid under ambient conditions, can be readily separated into a carbohydrate and a lignin faction. The lignin isolated from the latter fraction is generally termed as Lignophenol and has unique chemical and physical properties differed distinctly from other technical lignin. Attempts to further understand and improve the reactivity of Lignophenols for enhanced polymer applications constitute the basis of this proposed project..In this study, major factors of the phase-separation process affecting the properties of resulting Lignophenol will be thoroughly investigated. These include the type of biomass, phenols, and reaction conditions. The potential application of Lignophenols in making common thermoplastic composites with Polypropylene/Polyethylene/Acrylonitrile butadiene styrene will be extensively evaluated and compared with those derived from petroleum-based polymers. Finally, it is aimed at developing a modified Lignophenol, which would have a very high compatibility with those originated from the petroleum base..In summary, the outcome of this project would provide fundamental understanding in modification of Lignophenols for enhanced chemical properties as well as their potential applications in making thermoplastic polymers composites. Above all, the phase-separation process represents a total utilization of the whole lignocellulosic polymers, as the carbohydrate components can be recovered and converted into a variety of bio-based products including bio-ethanols.

在高分子材料需求量日益增长和石油资源日显紧缺的当前形势下，研究以木质纤维素资源部分取代石油高分子材料具有重要意义。目前，关于木质素如何在工程塑料中广泛应用的研究面临着如何改善和提高极性完全不同的木质素高分子和合成高分子之间的界面相容性差的难题。本研究拟采用相分离技术，分别以木质纤维素、工业木质素、酶解木质素为原料得到木质素基高分子木质素酚。通过对木质素酚的进一步结构调控，研究木质素酚及其不同改性产物与工程塑料的相容性以及对复合材料力学性能的影响。从而解决木质素目前尚未被广泛应用于材料领域所面临的熔融塑化加工困难、共混共聚相容性差等关键技术问题，以阐明天然高分子与合成高分子高效融合途径与机理，是材料科学与生命科学的交叉领域研究，研究成果将为开发新型生物质基工程塑料提供重要的基础数据，具有重大意义。

在高分子材料需求量日益增长和石油资源日显紧缺的当前形势下，研究以木质纤维素资源部分取代石油高分子材料具有重要意义。目前，关于木质素如何在工程塑料中广泛应用的研究面临着如何改善和提高极性完全不同的木质素高分子和合成高分子之间的界面相容性差的难题。本研究采用了相分离技术，分别以木质纤维素、工业木质素、酶解木质素为原料得到木质素基高分子木质素酚。详细地表征了各种木质素酚的性状和结构特征，并得出了碱木素等工业木质素也能通过相分离法增加活性官能团的数量，达到一定程度的活性化；通过对木质素酚的进一步结构调控，研究了木质素酚及其不同改性产物与工程塑料的相容性以及对复合材料力学性能的影响。找到了不使用任何一种偶联剂和添加剂能够提高PLA, PHB等工程塑料与木质纤维素成分复合物强度的方法，并有效地解决了界面相容性问题。在木质素的分离过程中，同时也注意了其他细胞壁组分半纤维素、纤维素及抽出成分的改性及利用问题，也得到了相应的可应用性结果，并发表了多篇相关论文。本研究的结果解决了木质素目前尚未被广泛应用于材料领域所面临的熔融塑化加工困难，提供了木质素和工程塑料的复合的成功例，是材料科学与生命科学的交叉领域研究，将为开发新型生物质基工程塑料提供重要的基础数据，具有重大意义。