材料期刊网

采用双酚A型环氧树脂E--44与有机硅环氧树脂ES-06的共混改性树脂体系 进行紫外光辐照聚合, 制备了光聚合含硅聚合物; 使用原子氧效应地面模拟设备对光聚合含硅聚合物进行原子氧侵蚀试验, 比较了试验前后试样的质量、表面形貌和成分的变化, 研究了原子氧的侵蚀机理. 结果表明, 在紫外光辐照固化后改性树脂的表面形成一层含C的氧化硅(SiOx)膜, 经原子氧暴露试验后进一步氧化转变为富含SiO2的保护膜, 具有较好的耐原子氧性能. 原子氧对含硅共混物的侵蚀是多种效应协同作用的结果, 以发生化学反应为主, 通过提氢、插入和置换等机理产生含碳挥发性物质和H2O等, 导致聚合物的质量损失. 生成的硅氧化物留在聚合物表面, 能有效地阻止原子氧对基底聚合物材料的进一步侵蚀.

The blended resin systems of bisphenol A epoxy resin E-44 and silicone-epoxy resin ES-06 were UV cured．And then the atomic oxygen (AO) exposure experiments were carried out．The changes in surface composition and morphology of the polymer sample before and after AO exposure had been followed by scanning electron mictrscoly (SEM) and X-ray photoelectron spectroscopy (XPS). The mechanism of the interaction of AO with the photopolymerized silicon-containing polymer was discussed. The results show that the sample surface had been incompletely oxidized to a silicon oxide (SiOx )film after UV irradiation polymerization． Based on SEM and XPS data， it may be proposed that AO exposure of the materials produces a SiO2 film at the surface of the sample, which can protect the underlying polymer from AO erosion．The mechanism of interaction of AO with the polymer is mainly chemical reactions involved H-abstraction, replacement or bond, leading to remove the organic portions of the polymer as volatile products and leave a silicon oxide surface coating.