LASER PYROLYSIS-GAS CHROMATOGRAPHY MASS-SPECTROMETRY OF 2 SYNTHETIC ORGANIC POLYMERS

The utility of near-IR laser radiation in thermal degradation studies of two synthetic organic polymers is investigated. Continuous wave, near-IR laser radiation (1064 nm) is used to thermally degrade poly-para-tert-butylstyrene:graphite (1:1) and linear polyethylene: graphite (1:1) mixtures in quartz tubes. Pyrolysates are cryogenically trapped and subsequently analysed by GC/MS. The thermal degradation of these polymers during laser pyrolysis (LPy) proceeds via the mechanisms of depolymerization and random scission which are comparable to conventional filament pyrolysis. The emissive graphite serves to increase the heat transfer to the polymers. Sample temperatures during these LPy experiments are estimated to approach 600-degrees-C. While many unknowns remain surrounding the interaction of laser radiation with organic solids, this preliminary work provides a satisfactory basis for future LPy studies aimed at better understanding complex, natural organic polymers such as occur in geological and biological materials.