PBO纤维多尺度增强体仿生构筑及其界面增强与原子氧防护机制

当航天器在低地球轨道中运行时，作为结构材料的PBO纤维/环氧复合材料不仅存在界面性能差的缺陷，还时刻面临原子氧的侵蚀。本项目基于多巴胺辅助共沉积技术，采用“一步法”和“两步法”仿生构筑具有不同结构的PBO纤维多尺度增强体，旨在不影响纤维本体强度的情况下，一次性解决这两大难题。通过改变共沉积体系组分，氧化石墨烯的尺寸及参与反应方式等因素，实现PBO纤维表面纳米组元的可控分布，充分发挥其强化效应。对PBO纤维/环氧复合材料的界面性能和界面抗原子氧侵蚀性能进行全面评价，结合界面相特性分析，建立“多尺度增强体制备工艺-界面相微观结构-复合材料性能”关联体系，揭示复合材料的界面增强与界面原子氧防护机制。本项目为实现先进聚合物基复合材料的结构/功能一体化设计、提升其在严苛太空环境中的使用性能奠定理论和实验基础。

When a spacecraft works in low earth orbit, PBO fiber/epoxy resin composite as structural material not only has the poor interfacial properties, but also faces the attack of atomic oxygen. In this project, to solve the two drawbacks, PBO fiber hierarchical reinforcements with different structures are fabricated without degrading the base fiber by "one-step" and "two-step" mussel-inspired methods based on dopamine assistant co-deposition technology. By changing the composition of co-deposition solution, the size and the reaction mode of graphene oxide, the controllable distribution of nano-components on the surface of PBO fiber can be realized, and their strengthening effects can be fully played. The interfacial properties and interface anti-atomic oxygen erosion properties of PBO fiber/epoxy resin composite are comprehensive evaluated, combining with the analysis of interphase characteristics, a "hierarchical reinforcement fabrication process-interphase microstructure-properties of the composite" correlation system is established, and interface strengthening and interface atomic oxygen resisting mechanism of the composite are revealed. This project lays theoretical and experimental foundation for the realization of the structure/function integration design of advanced polymer matrix composites and the improvement of their performances in severe space environment.