特定拓扑结构液晶聚合物及其功能材料的高效点击化学合成

Click chemistry is a modular synthetic approach which continues to receive much attention due to its numerous applications in bioconjugation and material chemistry. Considering the advantage of click chemistry on the modification of polymers after successful achievement of a polymerization process, synthesis of dendron-linear block copolymers with dendron molecule and liquid crystalline polymer as the building blocks is represent in this research proposal. Here, mesogen-jacketed liquid crystalline polymers (MJLCPs), in which bulky aromatic side groups are connected to the backbones via covalent bonds, is introduced as the building block of liquid crystalline polymer. Interplay between the thermotropic mesomorphic behavior and the microphase separation in the dendron-linear block copolymers is investigated and the impact of topological structure of the block copolymer on the aggregation structure and the mesomorphic behavior is highlighted. Besides, novel composites integrating chemically modified graphene (CMG) and MJLCPs were prepared via click chemistry. Physical π-π stacking interaction between CMG platelets and aromatic side groups in MJLCPs was identified as root cause for the enhanced thermal properties of the composites. By the combination of soft matter nature of MJLCPs and excellent electrical conductivity and mechanical properties of carbon materials, application of MJLCPs in functional materials is explored.

基于点击化学合成方法在复杂拓扑结构聚合物控制合成方面的优势及甲壳型液晶聚合物软物质性质在聚合物复合材料中的潜在应用价值，本研究课题拟以树枝状分子和甲壳型液晶聚合物为构筑单元，合成精确拓扑结构的树枝状分子-甲壳型液晶聚合物嵌段共聚物，研究聚合物拓扑结构、组成及物理因素（如温度、溶剂）等对有序分子聚集体结构和稳定性的影响及聚合物液晶微结构的可控调节；同时，将点击化学合成方法引入到功能液晶聚合物材料合成中，制备石墨烯/甲壳型液晶聚合物复合材料，将液晶聚合物软物质体系性质与碳材料优异的导电性及物理机械性能相结合，探索甲壳型液晶聚合物在功能材料中的应用。

基金资助项目利用甲壳型液晶聚合物可控制备的特点及其在聚合物复合材料中的潜在应用价值，探讨了基于液晶聚合物构筑单元的树枝状分子-液晶聚合物嵌段共聚物体系的有序分子聚集体结构及聚合物液晶微结构的可控调节。将液晶聚合物软物质体系的性质与碳材料优异的物理机械性质相结合，开展了石墨烯/液晶聚合物复合材料的制备及性能研究，研究表明，石墨烯的引入可以有效的改善侧链型液晶聚合物相转变过程中储能模量下降的问题。结合二维红外相关光谱，对复合物相转变过程进行了分子层面的探讨。