Phenols Fourier transform-infrared spectroscopy

Analyses of the chloroform-soluble extracts of the subbituminous coal by Fourier transform infrared spectroscopy (FTIR) showed the presence of a sharp carbonyl absorption peak (1800-1650 cm ) in the extracts from the parent coal and in those obtained at yields less than about 10% wt dmmf. The peak, which is attributed to ketones and carboxylates, disappeared at higher conversions (16). Whitehurst and co-workers (12) established that carbonyl- containing compounds, such as esters and carboxylates, can cleave under thermal treatment to produce CO, CO2 and phenols. They concluded that the evolution of these gases during coal liquefaction could originate from the decomposition of similar oxygen functionalities in the coal. 

Tejedor-Tejedor, M.L Yost, E.C. Anderson, M.C. (1990a) Characterization of benzoic acid and phenolic complexes at the goethite/ aqueous solution interface using cylindrical internal reflectance Fourier transform infrared spectroscopy. Part 5 Methodology. Langmuir 6 979-987... 

The remaining useful life evaluation routine (RULER) is a useful monitoring program for used engine oils. The RULER system is based on a voltammetric method (Jefferies and Ameye, 1997 Kauffman, 1989 and 1994). The data allows the user to monitor the depletation of two additives ZDDP and the phenol/amineH+ antioxidant. The RULER results were compared to other standard analytical techniques, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), total base number (TBN), total acid number (TAN), and viscosity to determine any correlation between the techniques (Jefferies and Ameye, 1997 and 1998). The test concluded that the RULER instrument can... 

Williams DT, Tran Q, Fellin P, et al. 1991. Evaluation of gas chromatography-Fourier transform infrared spectroscopy-mass spectrometry for analysis of phenolic compounds. J Chromatog 549(1-2) 297-311. 

Rodriguez, I. Bollain, M.H. Garcia, C.M. Cela, R. Analysis of structural isomers of polychlorinated phenols in water hy liquid-nitrogen-trapping gas chromatography-Fourier transform infrared spectroscopy. J. Chromatogr. A, 1996, 733, 405. 

Traditionally, flavonoids have been separated and analyzed by HPLC and gas chromatography (GC). However, recent developments of SFC may permit a more accurate and complete analysis of plant phenolic compounds. Supercritical fluid chromatography brings together the advantages of both HPLC and GC techniques because it may be readily employed in the analysis of nonvolatile and thermolabile compounds and provides facile coupling to detector technologies such as mass spectrometry and Fourier transform infrared (FT-IR) spectroscopy. In recent years, SFC has been used to separate flavonoid compounds, most of which are polymethoxylated flavones and polyhydroxylflavonoids. 

Ethylene-vinyl acetate copolymer, terpene-phenol resins, polyethylene oxide, PMMA and some of their blends were solution cast on basic (aluminium oxide) and acidic (hydroxylated glass) substrates. Fourier transform infrared reflection absorption spectroscopy (IRRAS) was used to determine both the nature and the free energy of interfacial adduct formation in the polymer/metal systems. A correlation between IRRAS and adhesive strength may be used to predict both the acid-base work of adhesion and the density of interfacial interacting sites. 14 refs. 

Fourier transform infrared speetroseopy (FTIR) is a modem method for last analysis of phenolic resins [204,226,227], the modilied products [33,148,183,214], the curing process [218], and the erosslinked products. Several FTIR techniques are useful in phenolic resin characterization. The simplest method is transmission spectroscopy. This method requires an optimum optical density of the sample. Soluble prepolymers and soluble products may be examined as solutions using solvents i.e. triohloromethane, that are reasonably transparent over the range of400-4000 cm. Absorbance measurements can also be made on a thin film prepared by casting from solution. Solid, insoluble products may be mixed with potassium bromide and compessed at room temperature to an optical clear disk that can measured using the transmission method. 

Fourier transform infrared (FTIR) studies of the poly(bis-phenol A-carbonate) (PC) - poly(e-caprolactone) (PCL) blend system are presented. This is a complex blend system containing two crystallizable polymers, with large differences in crystalline melting points and glass transition temperatures (Tg), which are compatible in the amorphous state. FTIR spectroscopy has proven to be an excellent technique with which to study these blends. Evidence for the presence of specific chemical interactions between the two polymers in the amorphous state, which infers compatibility, has been obtained. Furthermore, the crystallization of the components of this blend system are readily followed at room and elevated temperatures. Solvent and polymer induced crystallization and the role of the effective Tg of the amorphous phase of the blends in the crystallization of PC is discussed. 

SpGCtroscopy. Infrared spectroscopy (59) permits structural definition, eg, it resolves the 2,2 - from the 2,4 -methylene imits in novolak resins. However, the broad bands and severely overlapping peaks present problems. For imcured resins, NMR rather than IR spectroscopy has become the technique of choice for microstructural information. However, Fourier transform infrared (FTIR) gives useful information on ciuing phenolics (60). Nevertheless, IR spectroscopy continues to be used as one of the detectors in the analysis of phenolics by GPC. (see Vibrational Spectroscopy)... 

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