纤维素基质子型离子液体功能材料的可控制备、性质与应用研究

The design and application of natural polymers with targeted functionality is one of emerging research directions under the subject of polymer science so far. In this project, taking the advantage of the novel solvent system (superbase/DMSO/CO2)for cellulose and multidisciplinary cross connection, we propose a facile synthesis of cellulosic carboxylic protic ionic liquids through the mild reaction between cellulose and cyclic anhydrides catalyzed by the in situ superbase, which acted as important organocatalyst for the cellulose dissolution, also an important organocatalyst for the subsequent acylation reaction and a cationic component in the formed protic ionic liquids. With the successful construction of protic ionic liquids functionality onto cellulose, serials of applications are going to be studied, such as their organocatalytic performance in the aldol reaction and Knoevenagel condensation reaction when water and supercritical CO2 are used as solvents; their immobilization of Pd nanoparticles for hydrogenation of alkene and cinnamaldehyde; their ability for SO2 and PM2.5 absorption. The multi-scale structures of the new cellulosic functional materials will be indentified, and the relationship of the material structure and properties and functionality will also be identified and developed. On the basis of the experimental achievements, new theory for the controllable design and preparation of new cellulosic functional materials will be proposed. The findings in this project also provide new insight for the design and application of new polymeric functional materials. The successful enforcement of this project will provide new knowledge in cellulose chemistry, green catalysis, air clean and will promote the use of cellulose, also further contribute the harmonious development of society. Therefore, the project has both of significant scientific and social value..

天然高分子特定功能化并实现其高值化、多元化利用，是高分子科学学科的重要研究内容。本项目通过学科交叉融合，创新性提出以超强有机碱/DMSO/CO2为纤维素溶解与衍生化平台，通过有机功能催化纤维素与环状酸酐的原子经济型反应，原位、一步合成纤维素基质子型离子液体多功能材料，研究材料构建反应动力学律及其化学、物理结构性质；研究新功能材料在水相、超临界CO2相的有机功能催化性能及负载纳米金属Pd催化性能，吸附SO2及PM2.5性质，阐明新多功能材料功能区域多层次结构与有机功能催化及吸附性能之间的构效关系，发展新材料在绿色催化、纳米催化及气体净化等领域的应用，建立与发展纤维素基质子型离子液体多功能材料多层次结构可控制备与性质调控理论及制备技术。本项目的成功实施，为新功能材料设计与可控制备、纤维素高效利用提供理论指导，为实现节能减排、发展循环经济提供技术支撑，具有重要的科学价值与社会效益。

天然高分子特定功能化并实现其高值化、多元化利用，是高分子科学学科的重要研究内容而如何实现天然高分子有效功能体系的可控、绿色构筑是该领域最核心的关键科学问题。本项目通过学科交叉融合，以超强有机碱/DMSO/CO2为纤维素溶解与衍生化平台，充分利用其溶液性质，通过有机功能催化纤维素与环状酸酐的原子经济型反应，超强有机碱即作为纤维素溶解的溶剂组分，酸酐与纤维素酰化反应的有机功能催化剂及纤维素质子型离子液体的阳离子部分，(1)原位、一步合成纤维素基质子型离子液体多功能材料，系统研究了其反应动力学与结构可调控性，研究其水溶液的溶液性质，包括导电率、zeta电位等性质；（2）系统研究了纤维素基质子型离子液体有机电解质催化材料，水相催化Knoevenagel缩合反应为模型反应，阐明了其结构与催化活性之间的关系并提出了其催化反应机理；（3）系统研究了通过多元酸酐交联与原位金属离子吸附及还原策略，构建了纤维素基质子型离子液体/纳米Pd复合凝胶催化材料，建立了其可控制备方法学，系统研究了其物理、化学结构；以对硝基苯酚还原、当归内酯氢化制备伽马戊内酯为模型反应，研究了其作为催化剂的催化反应动力学，阐明了其结构与催化活性之间的相互关系；（4）以2-十二烷烯-1-基丁二酸酐与丁二酸酐组成混合酰化体系，发展了亲疏水性可调控的纤维素基质子型离子液体/纳米Pd复合凝胶催化材料的构筑方法，以烯烃氢化，肉桂醛氢化为模型应用，揭示了通过亲疏水性调控催化反应动力学规律；（5）发展了羧基功能化纤维素凝胶材料，通过金属离子交换与原位还原策略，合成了具有磁性可回收的羧基纤维素水凝胶限域的Fe3O4纳米粒子复合催化剂，系统表征了其结构，及研究了其作为催化剂催化过氧化氢降解有机染料罗丹明B（RhB）的催化性能，系统研究了反应动力学，揭示了材料结构与催化活性之间的相互关系。研究成果为新型纤维素功能材料的设计、可控构筑提供了重要得理论与技术支撑，拓展了纤维素得应用。