Fiber surface chromatography, inverse

The objectives of this paper are to demonstrate how monolayer adsorption isotherms can be obtained on carbon fiber surfaces by inverse gas chromatography (IGC), and to compare results of solid/gas adsorption with those of solid/Uquid wetting. This information is correlated with independent assessments of surface chemical functionality provided by wet chemical titrations and x—ray photoelectron spectroscopy (XPS). 

Lately the most frequently used technique for the determination of thermodynamic and acid/base characteristics is inverse gas chromatography [30,73-75]. In IGC the unknown filler or fiber surface is characterized by compounds, usually solvents, of known properties. IGC measurements can be carried out in two different ways. In the most often applied linear, or ideal, IGC infinite concentrations of n-alkane are injected into the column containing the filler to be characterized. The net retention volume (V ) can be calculated by ... 

Inverse Gas Chromatography (IGC) was applied to E-glass fiber surfaces modified by various silane coupling agents. Using homologous series of alcohol (acid) and amine (base) vapor... 

It was shown previously by a gas adsorption analysis (inverse gas chromatography) that the interactions between gas probe molecules and the cotton surfaces were strongly dependent on the presence of waxes and non-cellulosic residues on such surfaces. The present XPS study clearly confirms tliat the cotton fiber surfaces are totally covered by a wax layer and that this layer eannot be totally removed after treatment in hot ethanol for 6 hts, even if this method is still recommended for such an extraction. 

P.N. Jacob, J.C. Berg, Acid-base surface eneigy characterization of mrcrocrystalline cellulose and two wood pulp fiber types using inverse gas chromatography. Langmuir 10, 3086-3093 (1994). doi 10.1021/la00021a036... 

Gas chromatography studies of surface modified silicas provided new insight concerning the adsorption properties of new stationary phases [129]. Inverse gas chromatography (IGC) can be a useful tool to determine the adsorption properties of low surface area solids. The work done by Bakaeva et al. [130] is a good example of IGC use to study low-surface-area-silica glasses. In the cited paper Bakaeva et al. employed IGC to analyze the adsorption of butanol and hexane on E-glass fiber. 

Belgacem M.N., Gandini A., Inverse gas chromatography as a tool to chtnacterize dispersive and add base properties of the surface of fibers and powders Chapter 2, in Interfacial Phenomena in Chromatography (Ed. Pefferkom E.), Marcel Dekker, Inc., New York, 1999. 

Belgacem, M.N. Gandini, A. Inverse Gas Chromatography as a Tool to Characterize Dispersive and Acid-Base Properties of the Surface of Fibers and Powders— Surfactant Science Series—VoL 80 Pefferkom, E., Ed. Marcel Dekker, Inc. New York, 1999,41-124. 

K Tsutsumi, Y Abe. Determination of dispersive and nondispersive components of the surface free energy of glass fibers. CoUoid Polymer Sci 267 637-642, 1989. K Tsutsumi, T Ohsuga. Surface characterization of modified glass fibers by inverse gas chromatography. Colloid Polymer Sci 268 38-44, 1990. 

The aim of the present study is to determine by XPS the chemical surface characteristics of different types of cotton fibers and to compare these characteristics with thermodynamic surface properties (surface energy) of the fibers, previously determined by means of inverse gas chromatography (IGC) at infinite dilution[3,4] Three types of cotton fibers of different varieties and exhibiting different maturities and wax contents are analyzed as received (raw fibers) or after having been extracted (extracted fibers) in hot ethanol for 6h. These results are compared with those previously obtained by inverse gas chromatography analysis. 

Cordeiro N, Ornelas M, Ashori A, Sheshmani S, Norouzi H. Investigation on the surface properties of chemically modified natural fibers using inverse gama chromatography. Carbohy Polym 2012 87 2367-2375. 

Figure 5.24 shows the effect of oxidation on dispersive and polar components of surface free energy. Carbon fibers were exposed to plasma treatment in the presence of various ratios of CF4 and O2. The untreated sample and the samples exposed to a substantial concentrations of oxygen show increase in the polar component. High concentrations of CF4 gas reduced its dispersive component and converted the surface to a PTFE-like material as confirmed by XPS studies. " Acid-base interaction which results from polar interaction can be predicted from the inverse gas chromatography data. The basic relationship used in this type of studies is " ... 

M.A. Montes-Moran, J.I. Paredes, A. Martfnez-Alonso, J.M.D. Tascon, Surface characterization of PPTA fibers using inverse gas chromatography Macromolecules 35,5085-5096 (2002). doi 10.1021/ma020069m... 

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