AbstractA laser probe–molecular beam experimental technique devised to investigate the dynamic characteristics of polymer decomposition processes is described. Results are presented from application of the technique to the laser vaporization of pure poly(vinyl chloride) (PVC). Vaporization products are sampled directly from the source cell using modulated molecular beam mass spectrometry. Only signals arising from the PVC species in the molecular beam appear in the modulated mass spectra; background species from the residual gas are automatically rejected. Time‐resolved spectra provide information on the relative evolution characteristics of the PVC decomposition products. Hydrogen chloride, benzene, and toluene are found to evolve concurrently from the irradiated PVC sample. PVC monomer species are not detected in the laser‐vaporized products. The presence of loosely bound water in the sample is distinguished from the evolution of volatile decomposition products by its burst‐like release mode. The effect of plasticizer and flame retardant additives on the evolution characteristics of the laser‐vaporized species from PVC are also
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