芳纶纤维表面超薄纳米层结构的可控构筑及其抗紫外辐射性能研究

Aramid fiber is an important strategic raw material in China's national economy and national defense security field, however, it is difficult to be developed and utilized in aerospace due to its poor UV-resistance properties. Although surface modification is a key and effective way to improve its UV-resistance performance, the special structure of polymer molecules makes the surface chemically inert, which brings great difficulties to the surface functionalization of aramid fibers. In this project, a series of ultra-thin organic-inorganic hybrid composite films are constructed by chemical bonding on the surface of aramid fiber using ALD and MLD technology, under the premise that how the (ultraviolet) light is acting on the destruction mechanism of aramid fiber. The organic-inorganic hybrid composite film was used to block the transmission of electrons and free radicals, avoid the damage to the aramid fiber body. The interaction mechanism between the aramid fiber and the functional film was systematically studied, and the structure-activity correlation between the nano-layer structure and the UV-resistance property of the aramid fiber was investigated, especially the scale dependence of aramid fiber for UV resistance. A scientific model between the inorganic-organic hybrid composite film on the surface of aramid fiber and its UV resistance performance was established. We expect to reveal the key factors and internal laws of achieving excellent UV resistance of aramid fiber and provide theoretical guidance and practical basis for the fabrication of new anti-UV aramid fiber.

芳纶纤维是我国国民经济和国防安全领域重要的战略原材料，但抗紫外辐射性能差的特点制约其在航空航天中的应用。虽然表面修饰是改善其抗紫外辐射性能的有效途径，但芳纶分子特殊的聚集态结构和组成使其表面呈化学惰性，导致芳纶纤维表面难以有效功能化改性。本项目在明晰(紫外)光对芳纶纤维本体破坏机制的前提下，结合表面纳米层结构设计，利用ALD和MLD技术在芳纶纤维表面键合结构和成分高度可控的超薄有机-无机杂化复合薄膜，通过阻隔电子和自由基的传输，避免其对芳纶纤维本体破坏的基础上，系统研究芳纶纤维本体与超薄功能纳米层间的相互作用机制，探究功能纳米层结构与芳纶纤维抗紫外辐射性能间的构效关系，尤其是抗紫外辐射性能的尺度依赖性，并建立芳纶纤维表面功能纳米层与其抗紫外辐射性能间的科学模型。期望通过本项目研究，揭示实现芳纶纤维优异抗紫外辐射性能的关键因素和内在规律，为制备新型抗紫外辐射芳纶纤维提供理论指导和实践依据。

芳纶纤维是我国国民经济和国防安全领域重要的战略原材料，但抗紫外辐射性能差的特点制约了其在航空航天中的应用。本项目从结构上系统阐述了芳香族聚酰胺纤维材料极端环境下的劣化性能的聚集态结构层面的根本性原因及其惰性纤维内部分子骨架上缺陷态形成机制，创新了惰性纤维调控方法，通过表层埃-纳米级微纳尺度物化调控，实现了芳香族聚酰胺纤维抗紫外辐射性能的根本性改善，其在强紫外照射(紫外光强：4260W/m2)和高温(＞200℃)共同作用90分钟(相当于持续暴露在强烈的阳光下约17500 天)后，其力学拉伸强度仅下降~0.85% ，还展现出优异的耐水洗性能和较高的热和化学稳定性，解决了芳香族聚酰胺纤维表面惰性难修饰和耐强紫外辐照性能差的双重难题，为惰性纤维材料及制品开发提供了普适性的原则和研究思路，并为实际应用打下了坚实的基础。本项目学术论文10篇，其中，SCI收录论文8篇，EI收录论文2篇，申请专利3项，培养硕士研究生6人。