The KBr technique to obtain spectra of cotton cellulose has been applied satisfactorily to an investigation of physical and crystalline modifications and to changes resulting from oxidation. Several experiments to illustrate applications are described. The potential applications to investigations suggested in the literature are reviewed. It has been shown that infrared absorption spectra of cotton cellulose can be used to follow changes in hydrogen bonding by the classical method of observing the exact wavelengths of the O-H stretching vibrations. Degree of crystallinity can be measured quantitatively by use of ratios of intensities of preselected absorption bands. Oxidation changes can be followed only where such processes result in the formation of C = O groups per se in the oxidized cotton.

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SummaryThe infrared spectra from 2 to 12 microns of chloroform (solutions of several glycerides have been measured and studied with a view to possible analytical applications. These spectra are presented, and conclusions which can be obtained from their examination are reported in this paper.The principal bands, common to the spectra of all glycerides, have been tabulated with correlations of the vibrating groups which give rise to them. The analytical significance of the infrared spectra is considered in detail for three specific regions: a) the O−H stretching vibration region, about 3.0 microus; b) the C−O stretching vibration region, about 9.0 microns; and c) the 10.0‐micron region of C−H bending, about the C=C group.Analyses of these regions of the spectra indicate that infrared absorption can be used to detect and to determine mono‐, di, and triglycerides in admixtures and that the method for the determination of transisomers can, with modifications, be extended to include analysis of triglycerides.

The potassium bromide disc technique is being used for rapid, simple, and reproducible measurement of the infrared spectra, of modified cotton fibers, yarns, and fabrics. Applications of the procedure have demonstrated that chemical modification can be readily detected and identified and that the extent of treatment can be quantitatively estimated. Experiments have been designed to select bands most useful in investigations of cotton modified by esterification. etherification, or replacement reactions. The examples cited illustrate the potential usefulness of infrared absorption spectra to studies in this field. A list has been prepared of 50 infrared absorption bands (and correlations with vibrating groups which give rise to them) which summarize the spectral characteristics which have been found most useful in investigations of cottons modified by esterification, etherification, and replacement reactions.