Evolved Gas Analysis-Mass Spectrometry (EGA-MS) Using Skimmer Interface System Equipped with Pressure Control Function

摘要

A new evolved gas analysis-mass spectrometry (EGA-MS) equipped with a skimmer interface system and a pressure control function (PCF) has been developed successfully. The skimmer interface system based upon jet separator principle is constructed between a sample chamber surrounded by an electrical furnace and a vacuum chamber. Although the skimmer type is principally more excellent than a capillary type, it is a significant problem that the sensitivity of EGA-MS falls with increasing the temperature.The fall of detection sensitivity of EGA-MS depending on temperature rising has been remarkably improved by introducing the pressure control function (PCF). As the result of evaluating PCF by using the thermal decomposition of calcium oxalate monohydrate, the ionic intensities of the evolved gases increased more than twice. The new EGA-MS was applied to the thermal decomposition of zinc acetylacetonate monohydrate and polymethylmethacrylate (PMMA). It was confirmed that the more sensitive and precise gas analysis which prevented condensation of evolution gases and/or generation of by-products can be performed, by comparing with the capillary interface system of TG-MS.