On the Use of Electrospray Ionization and Desorption Electrospray Ionization Mass Spectrometry for Bulk and Surface Polymer Analysis

Abstract

Electrospray ionization (ESI) and desorption electrospray ionization (DESI) mass spectrometry were for the first time compared to investigate degradation products resulting from radiolysis of polyurethane (PUR) irradiated using accelerated electrons. First, DESI optimization was performed to obtain the best results in terms of sensitivity for surface polymer analysis. Then, a comparison was performed between DESI-MS and ESI-MS characterization of the degradation products of irradiated PUR with different doses up to 10 MGy. Similar results were obtained despite a lower sensitivity of DESI. Finally, DESI results obtained by direct surface analysis of irradiated PUR films as a function of depth were compared to bulk analysis results obtained by ESI. This comparison shows that degradation products of PUR are very comparable at the surface or within the polymer, confirming the radio-oxidation homogeneity.

Soft ionization mass spectroscopy: Insights into the polymerization mechanism

“…Soft ionization mass spectrometry provides information on the molecular degradation pathways 71, 233–245. MS can also be used to examine degradation products, for example, in work described by Tondi et al200 on oligomeric residues present in the cabonisation (900 °C) of polyflavonoid tannin‐formaldehyde‐furfuryl alcohol or in various HALS degradation studies on polymer coatings 246–249. Moreover, Pastor‐Perez et al168 has also used MALDI to prove that the incorporation of photosensitizer into a poly(glycerol) dendrimer leads to an increase in its photostability.…”

Desorption electrospray ionization ‐ orbitrap mass spectrometry of synthetic polymers and copolymers

“…For polymer analysis, the limits of this new ionization method, in terms of sensitivity, accessible mass range and the polymer range able to be analyzed, are not well‐known since only a small number of articles reports the use of this technique for polymers . Cooks et al published in 2006 the first report on the DESI technique applied to polymers .…”

“…Among different metal cations (Na + , K + , Li + , Cs + and Rb + ), Li + cation was found to be the most useful for the DESI‐MS/MS of the PEG oligomers. Lastly, Moulin et al recently investigated the degradation products (≤1000 g.mol − 1 ) of a polyurethane irradiated using accelerated electrons by direct DESI‐TOF MS analysis of polymer films …”

“…[18] For polymer analysis, the limits of this new ionization method, in terms of sensitivity, accessible mass range and the polymer range able to be analyzed, are not well-known since only a small number of articles reports the use of this technique for polymers. [19][20][21][22] Cooks et al published in 2006 the first report on the DESI technique applied to polymers. [19] The examples concerned three industrial polymers: poly(ethylene glycol) (PEG), poly(tetramethylene glycol) and polyacrylamide with average molecular weights up to 3000 g.mol À1 .…”

“…Lastly, Moulin et al recently investigated the degradation products (≤1000 g.mol À1 ) of a polyurethane irradiated using accelerated electrons by direct DESI-TOF MS analysis of polymer films. [22] Hence, literature reports DESI results on low molecular weight polymers only; the case of copolymers was never addressed. In this work, we selected various synthetic polymers as models with different molecular weights (four families of homopolymers and three copolymers).…”