✍ Scribed by Conway, D. C. ;Marak, Roman
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Two addition‐type polymers, polystyrene and polypropylene, and two condensation‐type polymers, poly(ethylene terephthalate) (Mylar) and poly(hexamethylene adipamide) (nylon‐6,6), were pyrolyzed directly in the ion source of a mass spectrometer by chemical ionization (CI) to reduce fragmentation. The spectra are relatively easy to interpret because most ion peaks occur at a mass corresponding to the ion formula M±H or M + 3H, where M is the formula of a fragment of the original polymer chain. Oligomer peaks were observed for the addition‐type polymers. The intensities of the protonated dimer and monomer were measured as a function of time for styrene (S) and propylene (P). It was found that essentially all the HS^+^2 was produced by the reaction of HS^+^ with S, but at least part of the HP^+^2 was formed by proton transfer to P~2~. The absence of the analogous reaction in styrene is presumably a result of the reduced volatility of S~2~.
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Several marine algae, belonging to the classes of brown, red and green algae, were investigated by pyrolysis-direct chemical ionization mass spectrometry. Factor-discriminant analysis techniques applied to the pyrograms enabled differentiation between these classes. Pyrograms indicated relatively hi