Measurements by inverse gas chromatography

In the case of polystyrene blends with poly(vinyl methyl ether) two phase behaviour was found for blends from various chlorinated solvents whereas single phase behaviour was found for blends from toluene The phase separation of mixtures of these polymers in various solvents has been studied and the interaction parameters of the two polymers with the solvents measured by inverse gas chromatography It was found that those solvents which induced phase separation were those for which a large difference existed between the two separate polymer-solvent interaction parameters. This has been called the A% effect (where A% = X 2 Xi 3)-A two phase region exists within the polymer/polymer/solvent three component phase diagram as shown in Fig. 2. When a dilute solution at composition A is evaporated, phase separation takes place at B and when the system leaves the two phase region, at overall... 

Katsanos, N.A. Gavril, D. Kapolos, J. Karaiskakis, G. Surface energy of solid catalysts measured by inverse gas chromatography. J. Colloid Interface Sci. 2003, 270 (2), 455-461. 

The dispersive component is associated with polymer-filler interaction and the specific component is associated with filler networking and agglomeration. The dispersive component of different fillers is more conveniently measured by inverse gas chromatography although it can also be measured by contact angle methods. The work of adhesion is given by the following equation, which has been modified to account for Fowkes theoiy. 

Papirer, E., Brendle, E., Ozil, F., and Balard, H. (1999). Comparison of the surface properties of graphite, carbon black and fiillerene samples, measured by inverse gas chromatography. Carbon, 37, 1265—74. 

Jaroniec, M. Madey, R. Physical Adsorption on Heterogeneous Solids Elsevier Amsterdam, 1988. Katsanos, N.A. Gavril, D. Kapolos, J. Karaiskakis, G. Surface energy of solid catalysts measured by inverse gas chromatography. J. Colloid Interf. Sci. 2004,270,455-461. Topalova, I. Katsanos, N.A. Kapolos, J. Vasilakos, Ch. Simple measurement of deposition velocities and wall reaction probabihties in denuder tubes. Atm. Environ. 1994,28, 1791-1802. 

AH can be measured by inverse gas chromatography, as follows. The solid analyte is installed in gas chromatography as a solid stationary phase, a solvent with known values of C and E is used as a probe, and specific retention volume v° is measured at different temperatures. Then Formula 2.3 is used to calculate the enthalpy change of the interaction with the stationary phase. 

With the glass flow techniques, the solubility of gases in polymers is obtained from gas flow measurements by inverse gas chromatography [15]. In this procedure, the polymer sample (glassy or molten) acts as the chromatographic stationary phase to measure retention times. 

Fig. 17. A schematic of the alkane line obtained by inverse gas chromatography (IGC) measurements. The relative retention volume of carrier gas required to elute a series of alkane probe gases is plotted against the molar area of the probe times the. square root of its surface tension. The slope of the plot is yielding the dispersion component of the surface energy of...

Yokoi Y, Yonemochi E, Terada K (2005) Measurement of surface glass transition temperature of amorphous cefditoren pivoxil granules by inverse gas chromatography. J Drug Deliv Sci Techol 15 439-442. 

Katsanos, N.A. Ihopoulou, E. Roubani-Kalantzopoulou, F. Kalogirou, E. Probability density function for adsorption energies over time on heterogeneous surfaces by inverse gas chromatography. J. Phys. Chem. B, 1999,103, 10228-10233. Gavril, D. An inverse gas chromatographic tool for the experimental measurement of local adsorption isotherms. Instrum. Sci. Technol. 2002, 30, 397-413. 

From the 1980s, the chromatographic broadening technique has been substituted in the literature by inverse gas chromatography (IGC). The two main IGC methods for the measurement of diffusion coefficients in liquids are packed column IGCP and capillary column IGCP ... 

Zhao, C. Li, J. Jiang, Z. Chen, C., Measurement of the Infinite Dilution Diffusion Coefficient of Small Molecule Solvents in Silicone Rubber by Inverse Gas Chromatography. Eur. Polym. J. 2006, 42, 615-624. 

In addition, surface oxygen complexes affect the surface hydrophobicity, which determines the hydrophobic interaction. Hydrophobic interaction or, more specifically, hydrophobic bonding, describes the unusually strong attraction between hydrophobic molecules and hydrophobic carbon surfaces. The surface hydrophobicity of carbon materials can be determined, for instance, by measuring their contact angle with test liquids of known surface tension, by inverse gas chromatography or by water adsorption. 

BON Bonifaci, L. and Ravanetti, G.P., Measurement of infinite dilution diffusion coefficients of 8-caprolactam in nylon-6/solvent at elevated temperatures by inverse gas chromatography, J. Chromatogr., 607, 145, 1992. 

FEN Feng, Y., Ye, R., and Liu, H., Measurement of infinite diluted activity coefficient of solvents in polymer by inverse gas chromatography method (Chia), Chin. J. Chem. Eng., 8, 167, 2000. 

Adsorption-desorption techniques are often used for the study of surface treatment or for the modelling of polymer/filler interaction. Adsorption is determined by gravimetric techniques or, recently, more frequently by inverse gas chromatography (IGC). The strength of the interaction is usually deduced from the measured retention time or volume [99, 100]. 

Ticehurst, M. D., Rowe, R. C. and York, P. Determination of the surface properties of two batches of salbutamol sulfate by inverse gas chromatography. Int.. Pharm. 111 241-249, 1994. Dove, J. W, Buckton, G. and Doherty, C. A comparison of two contact angle measurement methods and inverse gas chromatography to assess the surface energies of theophylline and caffeine. Int.]. Pharm. 138 199-206, 1996. 

M. Pyda, G. Guiochon, Surface properties of sUica-based adsorbents measured by inverse gas-soUd chromatography at finite concentration. Langmuir 13, 1020-1025 (1997). doi 10.1021/ la950541f... 

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