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Paper spray ionization coupled with a high-resolution time-of-flight mass spectrometer was applied to the analysis of 13 block and 2 random ethylene oxide/propylene oxide (EO/PO) copolymers as well as to standard samples of poly(ethylene oxide) and poly(propylene oxide) homopolymers. Paper spray mass spectra could be obtained rapidly and, unlike electrospray ionization, were not subject to contamination and sample carryover. For comparison, polyether samples were also measured on a MALDI/TOF system with ultrahigh mass resolving power. MALDI/high-resolution time-of-flight mass spectrometry exhibited single-charge ions characteristic of the polymer distributions whereas the paper spray mass spectra exhibited charge states ranging from one to six charges. Kendrick mass defect plots of the multiple-charge ions in the paper spray mass spectra exhibit isotopic splitting of the Kendrick mass defects, facilitating visualization of the number of charges in each series. The slope of the KMD plots can be used to estimate the percentage of ethylene oxide in the copolymers. In-source fragmentation permitted the distinction between block and random copolymers.

Cardanol and cardanol derivatives are among the most important biobased materials currently investigated in green chemistry, as renewable and promising building blocks in lieu of traditional raw materials from non renewable resources, in particular owing to the olefinic linkages on the C15 alkyl side-chain. Despite the increasing interest they arouse, analytical chemistry dedicated to cardanol and associated resins has been rarely reported in the literature, found even poorer when dealing with chromatography and mass spectrometry. In this work, a thorough molecular characterization was conducted using matrix assisted laser desorption ionization (MALDI) mass spectrometry, size exclusion chromatography (SEC), and SEC-MALDI coupling to gain insights into the composition of phenolated, epoxidized, and epoxidized phenolated cardanol. A nomenclature was proposed to properly describe the numerous species found in these materials, while simulations of the unsaturation patterns and their comparison with the detected patterns in MALDI-MS gave useful details about the phenolation treatment expected to occur on the polyunsaturated C15 side chain. Finally, the SEC-MALDI off-line coupling allowed SEC peaks to be deconvoluted by mass spectrometry and MALDI artefacts related to matrix adduction to be pointed out.