Fourier transform surface polymers

An example, Figure 9 is an SFM image of a Langmuir-Blodgett film. This film was polymerized with ultraviolet light, giving a periodicity of 200 A, which is seen in the associated Fourier transform. The low forces exerted by the SFM tip are essential for imaging such soft polymer surfaces. 

Infrared spectroscopy, including Fourier-transform infrared (FTIR) spectroscopy, is one of the oldest techniques used for surface analysis. ATR has been used for many years to probe the surface composition of polymers that have been surface-modified by an etching process or by deposition of a film. RAIR has been widely used to characterize thin films on the surfaces of specular reflecting substrates. FTIR has numerous characteristics that make it an appropriate technique for... 

Laser desorption methods (such as LD-ITMS) are indicated as cost-saving real-time techniques for the near future. In a single laser shot, the LDI technique coupled with Fourier-transform mass spectrometry (FTMS) can provide detailed chemical information on the polymeric molecular structure, and is a tool for direct determination of additives and contaminants in polymers. This offers new analytical capabilities to solve problems in research, development, engineering, production, technical support, competitor product analysis, and defect analysis. Laser desorption techniques are limited to surface analysis and do not allow quantitation, but exhibit superior analyte selectivity. 

Gaboury, S. R. Urban, M. W. Analysis of Gas-Plasma-Modified Poly(Dimethylsiloxane) Elastomer Surfaces. Attenuated-Total-Reflectance-Fourier Transform Infrared Spectroscopy. In Structure-Property Relations in Polymers Urban, M. W., Graver, C. D., Eds. Advances in Chemistry Series 236 American Chemical Society Washington, DC, 1993 pp 777-790. 

Castillo, E. J., Koenig, J. L., Anderson, J. M., Kliment, C. K., and Lo, J. Surface analysis of biomedical polymers by attenuated total reflectance-fourier transform infra-red. Biomaterials 1984, 5(4), 186-193. 

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. 

Therefore, X-ray photoelectron spectroscopy (XPS) [12, 16,17] and diffuse reflection infrared Fourier transform spectroscopy (DRIFT) [17] are used to analyse the chemical composition of the metal surface and the amount of the surface-bonded polymer after the adsorption processes. For the ZnO/PVFA-co-PVAm composites solvatochromic dyes were employed to evaluate changes in the surface polarity after the polymer adsorption [18-22],... 

Many other on-line detectors suitable for SEC columns as reviewed [154], including chemiluminescent nitrogen detection, dynamic surface tension detection, high frequency detection and Fourier transform infrared detection, can be applied to FFF the latter being capable of delivering polymer compositions online. 

Surface analysis is a big challenge for the modihed polymers. It is well known that hydrophilicity and hydrophobicity can be measured in terms of water adhesion tension (x°). x° greater than 30 dyne cm are designated as hydrophilic and x° less than 30 dyne cm are designated as hydrophobic (Ma et al., 2007). Attenuated total reflec-tance-Fourier transformed infrared spectroscopy (ATR-FTIR) and XPS are two widely used techniques for the analysis of surfaces of modihed polymers. ATR-FTIR is not very specihc to the polymer surfaces as the signals are a combination of surfaces and underneath. Therefore, XPS can be used for the surface analysis because this technique has much smaller sampling depth (typically, <10 nm) (Ma et al., 2007). 

In situ Fourier transform infra-red spectroscopy (FTIR) can be used to trace the appearance of surface-active groups on the polymer surface, and to characterize the insertion of counter-ions as a function of the doping level. 

In the present studies, a Fourier-transform infra-red spectrometer in attenuated total reflectance mode (FT-IR-ATR) was used to characterize the albuminated polymer membrane surface. FT-IR-ATR is a powerful surface analysis technique in which a spectrum of only a few micron thick surface layer is obtained. As albumin or enzymes were attached only on the surfaces of polypropylene, FT-IR-ATR technique was ideally suited for the their analysis. 

Long-term oxidative degradation of an ion-beam irradiated polymer was studied. Silicon oxide thin layers were deposited on the surfaces of high density polyethylene (HDPE) to suppress the oxygen permeation. HDPE samples irradiated with a C6+ ion-beam were stored up to 12 months after the irradiation and the evolution of the chemical structure was followed by micro-Fourier transform infrared (micro-FT-IR) spectroscopy. Silicon oxide layers were found effective to suppress the long-term oxidative degradation of the ion-irradiated polymer. 

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