Polymer films, plasma deposited analysis

X-ray photoelectron spectroscopy (XPS) was used for elemental analysis of plasma-deposited polymer films. The photoelectron spectrometer (Physical Electronics, Model 548) was used with an X-ray source of Mg Ka (1253.6 eV). Fourier transform infrared (FTIR) spectra of plasma polymers deposited on the steel substrate were recorded on a Perkin-Elmer Model 1750 spectrophotometer using the attenuated total reflection (ATR) technique. The silane plasma-deposited steel sample was cut to match precisely the surface of the reflection element, which was a high refractive index KRS-5 crystal. 

Analysis of Plasma Deposited Flurocarbon Coatings on Polymer Films and Wool Fibers... 

Figure 33.2 shows XPS spectra of the surfaces of the TMS plasma polymer film deposited on (Ar + H2) plasma-pretreated steel (a, b, c) and on O2 plasma-pretreated steel (d, e, f). As shown in the spectra, the surface of the plasma film is functional in nature with functional groups of C-OH, C=0, and Si-OH. Two films basically ended up with the same surface structure. This is also confirmed by XPS analysis of the film during the film aging in air after the film deposition, which indicated that the film surfaces were saturated with a fixed surface structure after a few hours of air exposure [4]. This is due to a well-known phenomenon that the residual free radicals of the plasma polymer surface reacted with oxygen after exposure to air [5]. Curve deconvolution of C Is peaks showed structures of C-Si, C-C, C-0, and C=0. The analysis clearly shows a silicon carbide type of structure, which is consistent with the IR results. The functional surfaces of TMS films provide bonding sites for the subsequent electrodeposition of primer (E-coat). 

It appears that the coating resists any removal operation such as Soxhlet extraction more strongly than a simple deposition without any pre-activation. Some radicals formed during the plasma treatment would probably react with the polymer film. Surface examination by XPS analysis [5] before and after washing with water (Table 12.3) and even with phosphate detergent (e.g., with one of the solutions usual in hospitals, such as RBS detergent, consisting of a mixture of... 

Ratner, B.D., Tyler, B.J., Chilkoti, A. (1993) Analysis of biomedical polymer surfaces polyurethanes and plasma-deposited thin films. Clin. Mater., 13, 71-84. 

Oran, U., Swaraj, S., Lippitz, A., Unger, W.E.S., 2006. Surface analysis of plasma deposited polymer films, 7. Plasma Processes Polym. 3, 288—298. 

This first systematic XPS analysis has shown that it is possible to sputter-deposit compounds whose surface properties (fluorine to carbon ratio, cross-linking and branching) can be varied over a large range of values, as it has already been observed for polymer films prepared by plasma polymerization. We note here that a film very similar to polytetrafluoroethylene... 

Buddy Ratner s interests include biomaterials, tissue engineering, polymers, biocompatibility, drug delivery, surface analysis, self-assembly, nanobiotechnology, RF-plasma thin film deposition and biomaterials education. He has participated in the launch of six companies based on technologies from his laboratory, and serves as a consultant for numerous other companies. 

According to the literature /10,11/ plasma polymer layers contain free radicals which will react with oxygen and water in the atmosphere. In order to examine this fact plasmapolymerized acetylene was deposited using nitrogen instead of air. The elemental analysis of these films revealed less oxygen dian those deposited in air. This proves that most of the oxygen is incorporated into the layer during plasma polymerization. 

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