Surface analysis techniques fibers

X-ray photoelectron spectroscopy (XPS) XPS is a surface analysis technique that can be used to ascertain surface elemental composition and types of bonds present on the surface. It is also a straightforward, easy, and non-destructive characterization technique. In XPS, different scan resolutions lead to different information. On the one hand, a low-resolution scan can provide the percent of each element, as well as their atomic concentrations. On the other hand, a high-resolution scan can give the types of bonds and concentrations on the surface. Take carbon (Cis) as an example, its high resolution scans can be divided into four components peaks around 285.0, 286.5, 228.0, and 289.5 eV. These subpeaks are Cl (C-C or C-H), C2 (C-OH), C3 (O-C-O or C=0), and C4 (0-C=0), respectively. XPS has frequently been applied to confirm the chemical changes of polymer or fiber after treatment. In addition. XPS can be used to verify the occurrence of surface... 

Another alternative technique, solid-phase microextraction (SPME), was used for the determination of fluoxetine [79] and several TCAs [80], SPME is a miniaturized and solvent-free technique, where analytes are extracted from the sample by adsorption on a thin polymer coating fixed to the solid surface of a fiber, located inside an injection needle or a capillary. Its main disadvantage is that special strategies are needed to couple SPME to the LC-MS analysis. 

Explicitly developed are models of several theoretical multiphase distributions, with corresponding depth-profile results on thin-film plasma polymers, phase-separated block copolymers, and chemical reactions on fiber surfaces. Ion impact is treated from three points of view as an analytical fingerprint tool for polymer surface analysis via secondary ion mass spectroscopy, by forming unique thin films by introducing monomers into the plasma, and as a technique to modify polymer surface chemistry. 

IR spectroscopy is a common analytical technique in the textile industry. IR is capable of identifying fibers and their additives, as well as showing quantitative blend ratios and additive contents. The ATR (attenuated total reflection) technique, especially in its multiple form, MIR (multiple internal reflection) is of special importance in this field. The sample preparation is simple and fast the cut out swatches with appropriate surface areas are placed against each side of the MIR crystal, ensuring sufficient and uniform contact across the crystal surface. The internal reflection methods are non-destructive, so that the sample may be saved for other types of analysis, they are, further, methods of surface analysis. This is advantageous in all cases where the finish resides primarily on the fiber surface. In this case, a very strong spectrum of the finish is obtained, with minimal interference from the base fiber (Hannah et al., 1975). 

In this work the first method for detection and quantification of a chemical agent s simulants on metallic surfaces using sample smearing on surface as transfer method was evaluated as a proof of concept experiment. Spectroscopic characterization of thin layer deposits was achieved using the powerful technique of Grazing Angle Probe-Fiber Optic Coupled-FTTR developed for surface analysis . This methodology relies on... 

Morita et al [2] have described the characterization of commercially available PAN based carbon fibers using SEM, TEM, EELS, XPS, Raman and FTIR techniques and there are many publications on surface analysis [3,4]. 

ABSTRACT. The paper details the use of scanning electron microscopy, surface reflectance infrared spectroscopy, Auger electron spectroscopy, ion scattering spectroscopy, secondary ion mass spectroscopy, and x-ray photoelectron spectroscopy in the analysis of polymeric adhesives and composites. A brief review of the principle of each surface analytical technique will be followed by application of the technique to interfacial adhesion with an emphasis on polymer/metal, fiber/matrix, and composite/composite adhesion. 

In summary, there are a number of microscopic/spectroscopic experimental techniques, of which only a limited number have been discussed above, which are readily adaptable to the characterization of polymer/metal, fiber/matrix, and composite/composite adhesion. Indeed, basic questions in adhesion science such as the mechanism of adhesion, bond durability and the composition of failure surfaces, can be addressed experimentally today with increasing confidence due to the availability of these techniques. The author and his associates have summarized (6,11-13,22,25,2634,36-62) the results of the application of surface analysis to polymer/metal, fiber/matrix, and composite/composite adhesion on systems stuped at Virginia Tech. 

The analysis of fibers by surface-specific techniques presents. some special problems which will be discussed in Sections 2.1-2... ... 

Although this technique is not normally used for thin polymer films for the reasons described before, it can be used for analyzing the surface of polymer composites containing conductive fillers, e.g. carbon fibers. In addition, because of the surface specificity, the sampled area can be maintained almost identically to the beam cross-section so that the scanning Auger microscope (SAM) can have a spatial resolution that is much better than that of microprobe analysis. 

SIMS is a technique of direct mass analysis where the ion sputter is removed from the surface and, as a result of the ion bombardment, it is analyzed. By measuring both positive and negative ions, two different types of mass spectra are obtained. Positive SIMS is especially sensitive to low Z elements, which have low electronegative and ionization potential, while the negative SIMS is most sensitive to low Z elements with high electronegativity. The SIMS spectrum shown in Fig. 2.14 (Denison et al., 1988a, b) as a function of mass number is typical of that obtained from a carbon fiber surface. 

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