聚酰亚胺表面有机-无机硅杂化/石墨烯抗原子氧防静电复合改性

随着低轨长寿命航天器的发展，聚酰亚胺（PI）表面抗原子氧防静电复合改性需求日趋迫切。针对一般防护涂层使用过程中脱落开裂导致防护失效的问题，本项目拟采用湿化学方法在PI表面构建有机-无机硅杂化/石墨烯（Gr）复合改性层来实现抗原子氧和防静电双重功能，利用γ-氨丙基三乙氧基硅烷（APTES）分别与PI和氧化石墨烯（GO）的化学键合作用及硅氧烷基团间的聚合反应，在界面间形成稳固连接，并通过APTES、四乙氧基硅烷（TEOS）、GO比例调控防护层组成结构，解决脱落开裂等问题。将结合量子化学计算与实验方法研究改性体系自身及其与PI基体的反应键合特性，阐明改性体系在PI表面的扩散反应和界面结合机理及其关键影响因素，并通过表面改性反应体系、工艺、组成结构与抗原子氧和防静电性能之间的关联性研究，揭示防护机理。本项目将为解决涂层使用过程中脱落开裂等问题提供理论和方法借鉴，促进PI多功能化和实用化发展。

With the development of long-life spacecraft in low Earth orbit, compounded surface modification of polyimide (PI) for atomic oxygen resistance and antistatic performance has become increasingly urgent. Generally, peeling and cracking occurred during the use of conventional protective coatings. In this project, organic-inorganic silica/graphene (Gr) composite coatings will be grafted to the surface of PI to achieve atomic oxygen resistance and antistatic performance by a facile wet chemical method. Stable bonding will be formed through reactions of γ-aminopropyltriethoxysilane with PI and graphene oxide (GO) as well as polymerization between the siloxane groups. Composition and structure of the coating will be adjusted through the ratio of APTES, tetraethoxysilane (TEOS) and GO to solve the problem of peeling and cracking. Quantum chemical calculations and experimental methods will be combined to investigate the bonding properties of the reaction system. The diffusion reaction and interfacial bonding mechanism of the modified system on the PI surface as well as the key influence factors will be discussed. The relationship between the technological parameters, composition, the structure and performance will also be studied, together with the failure mechanisms of the modified PI. This study will provide new clew for solving problems such as peeling and cracking during the use of general coatings and promote the development of multifunctionality and practicalization of PI.