A NEW METHOD FOR THE CHARACTERISATION AND CLASSIFICATION OF THE INFRARED TRANSMISSION PROPERTIES OF MATERIALS WITH HIGH MOLECULAR WEIGHT OR COMPLICATED COMPOSITION USING THE PRIMA METHOD (PATTERN RECOGNITION BY INDEPENDENT MULTICATEGORY ANALYSIS)

Abstract

In the present work multicomponent systems, in most cases natural samples were investigated with the purpose of identification, or determination of the chemical structure of the constituents. IR spectra of the samples were evaluated using the PRIMA (Pattern Recognition by Independent Multicategory Analysis) pattern recognition method. In the present report the application of the method to the identification of concrete additives, to the investigation of the degree of cross linking of dextran-based gel filters, and to studies on the chemical structure and composition of humic acids and tobacco plant parts is described. In some of the above cases the IR band positions are identical for all the samples, so new data, the relative absorbances calculated for some selected bands, have been introduced to quantitatively characterize the spectra. The method described is very simple and has proved to be very efficient in solving the problems outhived.