Characterization of network structure in radiation-cured resins of polyfunctional acrylic ester and N-vinylpyrrolidone by MALDI-MS combined with supercritical methanolysis

Abstract

The cross-linking structures of the ultraviolet and electron beam cured resins prepared from pentaerithritol triacrylate and N-vinylpyrrolidone (VP) mixtures were characterized by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) combined with supercritical methanolysis. The MALDI-mass spectra of the methanolysis products contained a series of peaks of sodium-cationized methyl acrylate/VP co-oligomers formed through selective cleavage and methylation at ester linkages in the radiation-cured resins, which reflected the cross-linking sequences. The composition distributions of the methanolysis products were interpreted in terms of curing conditions such as energy source, photoinitiators, dosage of radiation and formulations.