Li Yi, Li Zhonghua, He Yanchun, Wang Hu, Zhang Kaifeng, Yuan Lu, Cao Shengzhu, Ma Dongfeng, Li Lin, Yang Miao, Gao Hengjiao, Wang Kai, Xu Min, Li Detian
Science and Technology on Vacuum Technology and Physical Laboratory, Lanzhou Institute of Physics, Lanzhou 730000, China.
College of Textiles, Donghua University, Shanghai 201620, China.
ACS Appl Mater Interfaces. 2023 Oct 18;15(41):48810-48817. doi: 10.1021/acsami.3c10434. Epub 2023 Oct 6.
A flexible, dense, defect-free, highly adhesive, and highly dissociation energy-rich protective coating is essential to enhance the atomic oxygen (AO) resistance of polymeric materials in a low Earth orbit (LEO). In this work, a dense, defect-free hybrid HMDSO/SiO thin film coating with compositional gradients on the surface of polyimide was synthesized using vacuum-ultraviolet (VUV) irradiation. The effects of VUV irradiation on the morphology, optical transmittance, and chemical components of plasma-polymerized HMDSO (pp-HMDSO) thin-film coatings deposited on the polyimide surface were investigated in depth. There were no defects such as cracks and holes in the surface morphology of pp-HMDSO films after VUV irradiation, but the surface roughness increased slightly, and the corresponding optical transmittance decreased slightly. The chemical components of pp-HMDSO films were changed in the depth direction starting from the top of the surface, forming hybrid HMDSO/SiO thin films with compositional gradients. The component gradient HMDSO/SiO composite coating further enhanced the atomic oxygen resistance of the polyimide due to the surface layer of the UV-modified coating enriched with high dissociation energy SiO material. Therefore, this work provides a facile UV-induced synthesis method to prepare dense, defect-free, and highly dissociation energy-rich protective gradient coatings, which are promising not only for excellent AO protection in LEO but also for potential application in water-oxygen barrier films.
一种柔性、致密、无缺陷、高附着力且具有高离解能的防护涂层对于提高聚合物材料在低地球轨道（LEO）中的抗原子氧（AO）性能至关重要。在这项工作中，利用真空紫外（VUV）辐照在聚酰亚胺表面合成了一种表面具有成分梯度的致密、无缺陷的HMDSO/SiO混合薄膜涂层。深入研究了VUV辐照对沉积在聚酰亚胺表面的等离子体聚合HMDSO（pp-HMDSO）薄膜涂层的形貌、光学透过率和化学成分的影响。VUV辐照后，pp-HMDSO薄膜的表面形貌没有裂纹和孔洞等缺陷，但表面粗糙度略有增加，相应的光学透过率略有下降。pp-HMDSO薄膜的化学成分从表面顶部开始在深度方向上发生变化，形成了具有成分梯度的混合HMDSO/SiO薄膜。由于紫外改性涂层的表面层富含高离解能的SiO材料，成分梯度HMDSO/SiO复合涂层进一步提高了聚酰亚胺的抗原子氧性能。因此，这项工作提供了一种简便的紫外诱导合成方法来制备致密、无缺陷且具有高离解能的防护梯度涂层，这些涂层不仅有望在LEO中提供优异的AO防护，而且在水氧阻隔膜方面具有潜在应用前景。
