Characterization of Cross-linking Structures in UV-cured Acrylic Ester Resin by MALDI-MS Combined with Supercritical Methanolysis

Analysis of Acrylic and Methacrylic Networks through Pyrolysis-GC/MS

A direct analytical method developed to characterize UV-cured networks based on multi-step pyrolysis-gas chromatography-mass spectroscopy (GC/MS) is presented. Application of the method to characterize (meth)acrylate-based UV-cured networks is discussed. The reversion process of methacrylates is clearly observed during pyrolysis. In contrast, the decomposition of acrylates in high molecular weight degradation products is hardly detected. The potential impact of this technique to elucidate the structural and compositional nature of UV-cured polymeric networks is highlighted.

Characterization of the cross-linking structures in UV- and EB-cured acrylic copolymer resins using high resolution MALDI-spiral-TOFMS combined with supercritical methanolysis

The cross-linking structures of ultraviolet (UV) and electron beam (EB)-cured acrylic copolymer resins prepared with pentaerithritol triacrylate and 1-vinyl-2-pyrrolidone (VP) mixtures were characterized using high resolution MALDI-TOFMS combined with supercritical methanolysis.

Controlling the kinetic chain length of the crosslinks in photo-polymerized biodegradable networks

Biodegradable polymer networks were prepared by photo-initiated radical polymerization of methacrylate functionalized poly(D,L-lactide) oligomers. The kinetic chains formed in this radical polymerization are the multifunctional crosslinks of the networks. These chains are carbon-carbon chains that remain after degradation. If their molecular weight is too high these poly(methacrylic acid) chains can not be excreted by the kidneys. The effect of the photo-initiator concentration and the addition of 2-mercaptoethanol as a chain transfer agent on the molecular weight of the kinetic chains was investigated. It was found that both increasing the initiator concentration and adding 2-mercaptoethanol decrease the kinetic chain length. However, the effect of adding 2-mercaptoethanol was much larger. Some network properties such as the glass transition temperature and the swelling ratio in acetone are affected when the kinetic chain length is decreased.