Molecular structure of interfaces between plasma‐polymerized acetylene films and steel substrates
Molecular structure of interfaces between plasma‐polymerized acetylene films and steel substrates
复制标题
等离子体聚合乙炔薄膜与钢基材界面的分子结构
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
F. J. Boerio
中科院分区：
文献类型：
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作者：
Y. Tsai;F. J. Boerio
通过在氩载气中激发等离子体，然后将单体注入余辉区域，将乙炔的等离子体聚合膜沉积在感应耦合反应器中的钢基材上。使用反射吸收红外光谱 (RAIR) 和 X 射线光电子能谱 (XPS) 确定薄膜/基材界面的分子结构，以将薄膜表征为厚度的函数。 RAIR表明，厚的（~ 900 A）沉积等离子体聚合乙炔薄膜具有复杂的分子结构，包含甲基和亚甲基、单取代和二取代乙炔、乙烯基以及顺式和反式二取代烯烃基团。还获得了捕获的自由基与大气中的氧气和水分反应形成 O-H 和 C=O 基团而产生氧化的证据。薄膜 (∼ 60 A) 的分子结构相似，尽管有证据表明在薄膜/基底界面处存在乙炔基团 (H-C=C -)。使用角度分辨 XPS 分析获得的结果表明，碳质污染物从基底上去除，并且基底表面上的氧化物和氢氧化物，特别是 FeOOH，在薄膜沉积过程中被化学还原。XPS 还证实，沉积在钢基底上的等离子体聚合乙炔薄膜含有 C-O- 和初步结果还表明，在电感耦合反应器中沉积的薄膜是橡胶与金属粘合的良好底漆，而在电容耦合反应器中沉积的薄膜则不然。这种差异可能是由于前一种类型的薄膜中存在多种官能团，而后者则不然。
Plasma-polymerized films of acetylene were deposited onto steel substrates in an inductively coupled reactor by exciting the plasma in an argon carrier gas and then injecting the monomer into the afterglow region. The molecular structure of the film/substrate interface was determined using reflection-absorption infrared spectroscopy (RAIR) and X-ray photoelectron spectroscopy (XPS) to characterize the films as a function of thickness. RAIR showed that thick (∼ 900 A) as-deposited plasma-polymerized acetylene films had a complicated molecular structure and contained methyl and methylene, mono- and disubstituted acetylene, vinyl, and cis- and trans-disubstituted olefin groups. Evidence of oxidation resulting from the reaction of trapped radicals with atmospheric oxygen and moisture to form O-H and C=O groups was also obtained. The molecular structure of thin films (∼ 60 A) was similar although evidence was obtained to indicate that acetylide groups (H-C≡C - were present at the film/substrate interface. Results obtained using angle-resolved XPS analysis showed that carbonaceous contamination was removed from the substrate and that oxides and hydroxides on the substrate surface, especially FeOOH, were chemically reduced during deposition of the films. XPS also confirmed that plasma-polymerized acetylene films deposited on steel substrates contained C-O- and C=O groups. Preliminary results also showed that films deposited in an inductively coupled reactor were good primers for rubber-to-metal bonding, whereas films deposited in a capacitively coupled reactor were not. The differences may be due to the wide variety of functional groups found in the former type of films but not in the latter.