Utilising time-lag focusing ultraviolet-matrix-assisted laser desorption/ionisation mass spectrometry for the end group analysis of synthetic polymers

Time-lag focusing matrix-assisted laser desorption/ionisation-mass spectrom etry (MALDI-MS) has been employed to analyse synthetic polymers with averag e molecular weights between approximately 3500 and 12500 Da. Spectra are sh own that demonstrate the improvement in resolution and sensitivity when tim e-lag focusing is sued instead of prompt extraction techniques. A resolutio n of almost 9000 (FWHM) was obtained, in the reflectron mode of operation, for a poly(methyl methacrylate) PMMA) sample with a relatively narrow dispe rsion. The data for PMMA polymers of industrial relevance easily enables th e differentiation of many end groups as a consequence of the improved signa l-to-noise and good mass accuracy when time-lag focusing is employed.