具有交替多层结构的PVDF/PMMA多重形状记忆材料的构筑及其在形状记忆过程中微观结构的演变研究

With the broadening of the application of smart materials, designing and developing multi-shape memory polymers which can memorize more temporary shapes represent the new trend of this field. In this research proposal, a type of alternating multilayered PVDF/PMMA multi-shape memory materials will be fabricated by utilizing layer-multiplying co-extrusion technology. By controlling the layer numbers, the layer thickness ratio and the layer interfaces in layer-multiplying process, the relaxation of macromolecular chains in bulk and interfacial layers will be investigated, and the multi-shape memory will be realized with the formation of broad thermal transition range. The relationship between the layer structure/measuring conditions and the shape memory properties will be explored in depth and the multi-shape memory mechanism for alternating multilayered system will be proposed. Additionally, further studies focusing on the microstructural development induced by the stress-/temperature-field effect in the shape memory process and its influence on macroscopic properties will be fulfilled at last. In general, this research proposal will be carried out surrounding the interrelation of “fabricating alternating multilayered structure-tailoring the molecular relaxation-achieving shape memory properties”. The completion of this research will provide new thought and strategy to efficiently prepare multi-shape memory polymers and intelligently tailor their structure and properties, which will be of great significance to enrich and develop the material types and related theories.

随着智能材料应用范围的不断拓宽，设计和开发能够记忆更多临时形状的多重形状记忆聚合物代表着该领域发展的新趋势。本申请项目拟采用层倍增共挤出技术制备具有交替多层结构的PVDF/PMMA多重形状记忆材料。利用层倍增过程对层数、层厚比以及层界面的调控，研究各组分分子链在本体层和界面层的松弛运动行为，进而通过构筑宽热转变温域实现对多重临时形状的记忆；深入探索层结构和测试条件与材料形状记忆性能的关系，建立交替多层体系的多重形状记忆机理；在此基础上，进一步研究材料在形状记忆过程中各组分内在多层次结构在应力和温度场作用下的演变规律及其对宏观性能的影响。本项目围绕“交替多层结构构筑-链段松弛运动调控-形状记忆性能实现”之间的相互关系开展研究，将为多重形状记忆聚合物的高效制备以及聚合物结构和性能的智能化调控提供新的思路和方法，对丰富和发展多重形状记忆材料种类及相关理论具有重要意义。

形状记忆材料是智能材料的重要组成，随着社会经济的发展其受关注度和应用需求正越来越大，而设计和开发能够记忆更多临时形状的多重形状记忆聚合物代表着该领域发展的新趋势。本项目团队采用自主研发的层倍增共挤出技术制备了一系列具有交替多层结构的PVDF/PMMA多重形状记忆材料。利用层倍增过程对层数、层厚比以及层界面的调控，研究了各组分分子链在本体层和界面层的松弛运动行为，进而通过构筑宽热转变温域实现对多重临时形状的记忆；探索了层结构和测试条件与材料形状记忆性能的关系，建立了交替多层体系的多重形状记忆机理；在此基础上，进一步研究了材料在形状记忆过程中各组分内在多层次结构在应力和温度场作用下的演变规律及其对宏观性能的影响。四年来，团队成员在Chem Eng J, Macromolecules, ACS Appl Mater Interface, Polymer等期刊发表项目相关学术论文10篇（SCI收录9项），获授权中国发明专利3项，受邀撰写英文专著1章。相关成果为多重形状记忆聚合物的高效制备以及聚合物结构和性能的智能化调控提供了新的思路和方法，对丰富和发展多重形状记忆材料种类及相关理论具有重要意义。