MASS-SPECTROMETRIC ANALYSIS OF RUBBER VULCANIZATES BY LASER DESORPTION LASER IONIZATION

Three different vulcanized rubbers have been studied by laser desorption/laser ionization man spectrometry. Analysis of these vulcanizates by various conventional mass spectrometric methods has been difficult because of the complexity of their mass spectra. The major thrust of the present work is to show that different wavelengths for the postionization step allow selectivity which provides important additional information about the chemical makeup of these complex materials. Near-UV wavelengths selectivity ionize aromatic additives, far-UV wavelengths photoionize other nonaromatic species, and VUV wavelengths access all of the desorbed species. The ability to vary these different parameters allows a specificity that rivals other techniques for surface and bulk analysis of polymers and their additives.