纳米粒子聚合物的表面引发可控聚合及功能化

Polynanomers are chains of strongly interacting inorganic nanoparticles, so called "nanomers", which can be viewed as monomers. Currently, polynanomers can be obtained by the polymerization of nanomers via interface polycondensation, step-growth homopolymerization, step-growth copolymerization, and chain polymerization. However, none of these methods can yield polynanomers with well-defined architectures, such as controlled degree of polymerization, narrow distribution, and ordered sequences. The lack of a polymerization method for well-defined polynanomer hinders the study of the correlation between structures and properties, as well as the development of functional polynanomers for potential applications. Herein, we propose to develop a method to apply strategies from surface-initiated-polymerization to the co-assembly of nanoparticles with different size and compositions. By the combination of guest-host supramolecular interaction and layer-by-layer assembly strategies, we will be able to synthesize polynanomers with controllable sequences, targeted degrees of polymerization, and narrow distribution of chain lengths. We will study their structure-property relationship. Furthermore, we will achieve the hierarchical assembly of copolynanomers by using stimulus-response nanomers and explore their potential applications in the field of environmental/biosensors.

"纳米粒子聚合物"是一种以无机纳米粒子作为单体，通过"聚合反应"而获得的一种新型的高分子材料。现已报导的纳米粒子聚合方法包括：界面缩聚反应、逐步均聚反应，逐步共聚反应共聚、链式聚合。然而，这些聚合方法都无法制备具有指定聚合度的、单分散的、且构型、构象可控的纳米粒子聚合物。可控聚合方法的缺失严重阻碍了对这种新型聚合物结构与性质对应关系的研究及其功能性的开发。本项目借鉴现代高分子化学可控聚合的思想，通过主客体识别相互作用，利用层层组装技术，从而实现纳米粒子的"表面引发可控聚合"反应，构筑单分散的、链长和序列可控的纳米粒子共聚物。进一步应用表面等离子纳米粒子的光响应性，实现聚合物的多级组装。系统研究其在高分子及纳米材料方面的特殊性质及其形态结构与新型综合性质之间的关系，并初步探索功能性纳米粒子聚合物在生物环境检测、新材料等应用。

纳米粒子聚合物因其以无机纳米粒子作为链段的重复单元而表现出与有机高分子不同的性质。已报道的无机纳米粒子聚合物所使用的单体类型单一，聚合物链结构难以调控，限制了对纳米粒子聚合物性质及应用的研究。为了解决这一关键科学问题，本项目设计合成新型形状可控的无机纳米粒子单体，发展了一系列精准可控合成具有特殊拓扑结构和官能度的纳米粒子单体的方法，通过调节、表征、分析聚合物配体表面接枝链密度、表面分布位置、嵌段聚合物配体的相分离行为，从而实现更加可控的纳米粒子聚合反应，并且利用多种手性有机配体，构筑近程和长程有序的纳米粒子手性聚合物，阐释纳米粒子链段的手性结构与光学活性之间的关系，获得具有极高圆二色信号的纳米手性材料。本项目执行期间共发表SCI 论文10 篇，撰写英文专著的一章节，申请中国发明专利3 项，培养研究生5人。