Determination of the Ester Composition of Neopentyl Polyol Ester Lubricants

摘要

Methods of gas-liquid chromatography and thin-layer chromatography have been applied to the analysis of neopentyl polyol ester lubricants. By direct programmed-temperature gas chromatography of the lubricants, the components were separated according to volatility; in most cases resolution was adequate for semiquantitative analysis. Gas-liquid chromatographic analysis of the free acids produced by hydrolysis of the sample revealed the acyl composition. The parent polyols were determined by programmed-temperature gas chromatography of their valerate esters. A semipreparative thin-layer chromatographic method permitted the isolation of the three main ester types--trimethylol propane, pentaerythritol, and dipentaerythritol for further analysis. By a combination of these analytical methods the actual ester composition of the lubricant may be determined. Such detailed information had not previously been accessible by analytical procedures. (Author)