聚乙烯/碳纳米管(CNTs)复合材料是未来空间辐射防护结构材料的理想选材，在空间辐射环境下受到损伤，会导致结构与力学性能发生变化，影响其辐射防护效果。空间低能电子（<200 keV）是重要的辐射环境因素，深入研究聚乙烯/CNTs复合材料低能电子辐致力学损伤效应与机理，具有重要的学术价值和实际意义。国内外已有相关研究多偏于力学性能指标变化的定性评价，尚缺乏针对辐致微观结构变化与力学行为内在关系的研究。本项目以低密聚乙烯(LDPE)/多壁碳纳米管(MWCNTs)复合材料为研究对象，基于同步辐射X射线散射技术、原位拉伸试验及多种材料测试手段，深入研究低能电子能量和注量对LDPE/MWCNTs复合材料微观结构与拉伸变形行为的影响规律，揭示该材料低能电子辐致力学损伤效应的特征与机理，建立相应物理模型，为聚合物/CNTs复合材料的优化设计和成功用于空间辐射防护结构材料提供理论依据和技术支持。

Polyethylene/carbon nanotubes (CNTs) composites as a kind of structural material for space radiation shielding are very promising. In the space irradiation environment, the composites are sensitive to radiation damage which changes their microstructure and mechanical performance, directly affecting their shielding effectiveness. Low energy electrons (<200 keV) are important radiation environmental factors. Effects and mechanisms for mechanical damage of polyethylene/CNTs composites induced by low energy electrons will be studied, which has important academic value and practical significance. Previous research mainly involves the qualitative evaluation of the changes in the mechanical performance index. The inner relationship between microstructural changes induced by radiation and mechanical behaviour has not been deeply researched so far. In this project, low-density polyethylene (LDPE)/ multi-walled carbon nanotubes (MWCNTs) composites are chosen as research object. Effects of energies and fluences for low energy electrons on microstructure and tensile deformation behavior of the LDPE/MWCNTs composites will be investigated by an in-situ synchrotron radiation combined with tensile test and various material analysis methods. Basic characteristics of effects and mechanisms for mechanical damage of LDPE/MWCNTs composites induced by low energy electrons are revealed. Physical model of effects for mechanical damage of LDPE/MWCNTs composites induced by low energy electrons is built. These results could provide a theoretical basis and technical support for the reasonable design and successful application of CNT-based polymer composites as structural material for space radiation shielding.