Capillary Supercritical Fluid Chromatography/Mass Spectrometry of Phenolic Mannich Bases with Dimethyl Ether Modified Ethane as the Mobile Phase

Abstract

The analysis of phenolic Mannich bases [Formula: see text] which are used as hardeners and accelerators for epoxy resins [Formula: see text] by capillary supercritical fluid chromatography (SFC) with dimethyl ether modified ethane as the mobile phase is described. The elution properties of several different mobile phases with respect to amines are shown. SFC with UV detection is coupled via a custom-built interface to a mass spectrometer with atmospheric pressure chemical ionization. Two technically important Mannich bases prepared by different production processes are characterized and compared with respect to their byproducts. The role of dimethyl ether during the ionization process and the fragmentation of phenolic Mannich bases is discussed.

Supercritical Fluid and Unified Chromatography

“…A relatively uncommon mobile-phase mixture, ethane modified with dimethyl ether, was used by Fuchlueger et al for the capillary SFC of phenolic Mannich bases (86). These bases are used as hardeners accelerators for epoxy resins.…”

Fluidos supercríticos em química analítica. II. Cromatografia com fluido supercrítico: instrumentação

“…Com este ponto de vista, a SFC tornou-se interessante novamente. A maior parte dos trabalhos em SFC-MS com ionização à pressão atmosférica (API) têm sido realizados com colunas capilares [39][40][41] . Para a interface SFC com fonte API, equipamentos LC-MS comerciais foram usados sem modificações, requerendo somente a introdução de um restritor.…”

“…Alguns problemas podem surgir quando o instrumento apresentar um restritor não apropriado. Uma limitação no uso de fonte API está na utilização de uma composição programada (gradiente) da fase móvel em SFC 39,40 .…”

Separations Combined with Mass Spectrometry

“…Although the majority of the papers reporting on SFC−MS since 1995 have focused on optimizing interface designs using commercially obtained standards, there have been several applications reported. Broadbent et al have used SFC−MS in the analysis of photoproduct formation from the sunscreen component 2-ethylhexyl- p -methoxy cinnamate, SFC−MS has been employed in the analysis of phenolic Mannich bases used in epoxy resins by Fuchslueger et al, and the separation of thiohydantoin derivatives prepared as part of a combinatorial library has been reported by Ventura et al Although several combinatorial library applications have been reported at conferences, few have appeared in the refereed literature, possibly due to patent concerns.…”