多重氢键键合的超分子聚酯的物理老化及后续结晶行为的研究

Supramolecular polymers are a novel class of polymeric materials with wide application prospects, and the physical performance of such materials relies deeply on the physical aging in their service behavior. Therefore, it is urgent to analyze the principle of physical aging of supramolecular polymers and clarify its relationship with condensed structure and performance. Due to the confinement effects of supramolecular units, intersegmental and microphase separation of supramolecular units in polymer matrix on the segment mobility, the physical aging of supramolecular polymers differs from conventional polymers. In this project, we would like to select supramolecular poly(lactic acid) and poly(ethylene terephthalate) bonded by multiple hydrogen bonds as model systems and plan to systematically investigate the physical aging and subsequent crystallization of supramolecular polymers. Effects of the incorporation of supramolecular units, non-covalent interactions between polymer segments on aging kinetics and the evolution of chain conformation and microstructure during physical aging will be investigated and the mechanism will be discussed. The correlations of microstructure formed during physical aging process with subsequent nucleation and crystallization kinetics, nucleation mechanism will be illustrated. The results are expected to build up new methods to control macroscopic performance based on motion and crystallization of chain segments and provide theoretical basis for structural design, performance prediction and condition optimization of supramolecular polymer.

超分子聚合物是一类具有广阔应用前景的新型高分子材料，其服役行为中的物理老化对性能起决定作用，因而亟需深入解析超分子聚合物的物理老化规律及其与结晶凝聚态结构-性能之间的关系。由于超分子单元的引入，链间相互作用及超分子单元在基体中的微相分离会抑制聚合物的链段运动，超分子聚合物的物理老化与传统聚合物有所不同。本课题拟以多重氢键键合的超分子聚乳酸和超分子聚对苯二甲酸乙二醇酯为模型，系统研究材料在不同条件下的物理老化及后续结晶。研讨超分子单元的存在、链间相互作用对老化动力学及物理老化过程中链构象、微观结构演变的影响规律和机理，揭示物理老化过程中的构象和结构演变与后续结晶动力学、成核形式、成核动力学之间的关联。本研究将建立基于分子链段运动及结晶调控宏观性能的新方法，为超分子聚合物材料的结构设计、性能预测、条件优化等提供理论基础。

超分子聚合物是一类具有广阔应用前景的新型高分子材料，亟需深入解析超分子聚合物的物理老化规律及其与结晶凝聚态结构-性能之间的关系。本项目以聚乳酸为构筑基元，制备一系列多重氢键、金属配位作用键合的超分子聚合物，系统研究超分子聚合物的物理老化行为及其后续自修复、形状记忆和结晶行为。研究成果包括：（1）制备出一系列不同超分子单元含量及拓扑结构的超分子聚乳酸，阐明非共价键相互作用对超分子聚合物老化动力学及物理老化过程中结构演变的影响规律和机理；（2）揭示物理老化过程中的结构演变与后续结晶动力学、成核形式、结晶结构之间的关联；（3）建立基于物理老化条件改变分子链段运动及结晶调控超分子聚合物宏观性能的新方法；（4）构筑金属配位键合的超分子聚合物体系，研究金属离子种类与物理老化条件协同调控超分子聚合物性能的作用机制。项目执行期间，发表科技论文10篇，其中SCI文章9篇，核心中文期刊1篇，申请国家发明专利10项，授权发明专利5项。